Fertilizing time and method for cypress vine: mainly use dilute fertilizer water, and never overdo it
Cypress vine has relatively strong stress resistance, and its ability to adapt to the environment is also very outstanding. Its demand for nutrients is relatively loose, but when we grow it in pots or at home, we still need to pay attention to scientific fertilization, otherwise cypress vine will develop yellow leaves due to lack of fertilizer
Cypress vine has relatively strong stress resistance, and its ability to adapt to the environment is also very outstanding. Its demand for nutrients is relatively loose, but when we grow it in pots or at home, we still need to pay attention to scientific fertilization, otherwise cypress vine will develop yellow leaves due to lack of fertilizer. So how do you fertilize cypress vine? Let's learn about it together with the editor.
Does cypress vine need fertilizer
Cypress vine's demand for nutrients is relatively ordinary. If the soil is fairly fertile, it can generally meet its growth needs, but after all, the nutrients contained in the soil are limited. Therefore, to ensure that nutrients remain sufficient throughout its growth process, we need to fertilize in time. This point is equally key in the cultivation methods for cypress vine.
How to fertilize cypress vine
1. Choice of fertilizer
Plant growth cannot be separated from three main elements, namely nitrogen, phosphorus, and potassium, and the demand for these three nutrients differs at different growth stages. For example, the seedling stage mainly needs nitrogen, while before the flowering period the demand for phosphorus is relatively high. So generally choose compound fertilizer or fully decomposed organic fertilizer, etc., and it is best to dissolve it in water and dilute it into dilute fertilizer water before applying.
2. Fertilization method
1. Spring and autumn
Under normal circumstances, in these two seasons, apply dilute fertilizer water once a month. Dilute the fertilizer with water before use, which can ensure the concentration is not too high and will not burn the roots. In addition, the fertilizer chosen must be fully decomposed; cypress vine is relatively afraid of raw fertilizer.
2. Summer
We know that cypress vine likes high-temperature environments. Summer is the stage when it grows relatively fast. At this time, the fertilization frequency can be adjusted to once every 15-20 days, also mainly liquid fertilizer. Of course, if cypress vine is growing relatively well, the fertilization frequency can be appropriately reduced.
3. Winter
Except for a few areas in the south, temperatures in other places drop considerably in winter, and cypress vine's demand for fertilizer is basically zero. Therefore, fertilization is generally stopped in winter. Only a small amount of watering is needed to keep cypress vine's leaves green. Fertilizing instead will have the opposite effect.
3. Precautions
1. Each time you fertilize, the fertilizer should not come into direct contact with the plant, especially not be applied directly near the roots, because doing so can easily burn the roots. The correct method is to apply the liquid fertilizer into the soil along the edge of the flowerpot, so that the nutrients in the soil are slowly absorbed by the cypress vine's roots.
2. The fertilizer concentration does not need to be too high, and the amount used must not be too much. When growing plants, the thing most feared is excessive fertilization. This is one of the problems that many beginners easily encounter. To avoid this problem, you can use a small trick: apply a little less fertilizer at one time and do it more often.
Practical Complete Guide to Home Flower Growing (Part 2)
31．What are the benefits of root-outside fertilization？
Root-outside fertilization, also called foliar fertilization, is a fertilization method in which a diluted solution of chemical fertilizer or trace elements is sprayed on the leaf surface and absorbed and utilized by the plant through the leaf stomata. The main advantages of root-outside fertilization are: small dosage, remarkable and rapid fertilizer effect, it will not be fixed by the soil, and it is not affected by the absorption function of the root system.
32．Why can't undecomposed fertilizer be applied？
Some flower enthusiasts often bury rotten eggs, internal organs of chickens, ducks, and fish, meat skins, raw horse manure, cake fertilizer, etc. into the potting soil. They originally thought this could increase nutrients and make the flowers bloom profusely and the leaves lush, but the result is contrary to their wishes and instead harms the flowers. Why is this? Because the growth and development of flowers relies on absorbing various nutrient elements such as nitrogen, phosphorus, potassium, magnesium, and iron dissolved in water after fermentation in the soil, while the above-mentioned spoiled foods are buried directly into the pot without fermentation. After application, when they encounter water, they ferment and generate high temperatures, which will directly scald the flower roots. In addition, microbial activity causes soil oxygen deficiency, leading to the death of the flowers. At the same time, undecomposed fertilizer produces a foul odor during fermentation, attracting flies to lay eggs. Maggots can also bite the root system, harming flower growth, and the odor can also pollute the environment. Therefore, when growing flowers, one must pay attention to applying fully decomposed fertilizer to ensure good flower growth.
33．What harm does applying concentrated fertilizer do？
Applying liquid fertilizer with too high a concentration often causes flower branches and leaves to wither and turn yellow, and even the whole plant to die. What is the reason for this? Because under normal circumstances, the concentration of the cell sap of plant root hairs is greater than the concentration of the soil solution, so the osmotic pressures of the two differ. At this time, the soil solution can continuously penetrate into the root hair cells, and the root hairs can absorb water and nutrients from the soil to supply the growth and development of the flowers. If the concentration of the liquid fertilizer applied is too high (its concentration is greater than the depth of the cell sap), a reverse phenomenon will occur, that is, the cell sap instead penetrates into the soil solution, causing the root cells to lose water, causing plasmolysis, and in severe cases causing the plant to wither and die. The principle is similar to pickling vegetables at home. Put salt and vegetables into a water vat, and before long, the salt water becomes dilute and the vegetables become wilted. This phenomenon mostly occurs when too much chemical fertilizer is applied. If the retted liquid fertilizer applied is too concentrated, a similar phenomenon will also occur. Therefore, the concentration of chemical fertilizer solution applied to potted flowers must not be too high, generally around 0.1% is appropriate. When applying retted liquid fertilizer, it also needs to be diluted 5-10 times to be safe.
Practical Complete Guide to Home Flower Growing (Part 2)
34．Why are eggshells and tea dregs harmful to flowers？
In daily life, some people like to place eggshells in flowerpots or use leftover tea to water flowers, thinking this is beneficial to flower growth, but in fact it often does the opposite. Because when eggshells are placed on the flowerpot, the remaining egg white inside the shell flows into the surface layer of the potting soil, and after fermentation generates heat, directly burning the plant roots. At the same time, after the egg white ferments, it produces a foul odor, attracting flies to breed maggots, which bite the roots, and then easily induce the occurrence of pests and diseases, affecting flower growth. Tea contains theophylline, caffeine, and other alkaloids, which have a relative destructive effect on organic nutrients in the soil. At the same time, leftover tea covering the pot surface will gradually ferment and rot over time, hindering air permeability of the potting soil, causing oxygen deficiency in the pot, affecting root respiration, and being unfavorable to flower growth. However, after retting eggshells, taking the supernatant as a top dressing, or baking the eggshells dry and crushing them and applying them into the potting soil, is beneficial to flower growth and development. Retted tea dregs used as base fertilizer are also beneficial for soil improvement. The flower proverb "Seven parts depend on management, three parts depend on pruning" is an important experience in flower growing. Through pruning, not only can the distribution of flower branches be made uniform, nutrients be saved, plant vigor be regulated, and excessive growth be controlled, thereby making the flower plant shape neat and the posture graceful, but more importantly, it is conducive to more flowering. The flowers of most flowers bloom on new branches. Only by continuously pruning old branches can new branches be promoted, more flowers bloom, and more fruits be produced.35.What effect does air humidity have on the growth of foliage plants？
The water needed by foliage plants is easy to solve during watering. The difficult part is their special requirement for air humidity. Because most of them originate from tropical rainforests, they require air humidity of at least about 60%. Therefore, air humidity is an important factor in keeping the plant green and leafy. In northern indoor spaces, relative humidity is mostly below 60%. Under general conditions, as long as it is not lower than 50%, most varieties can still grow normally. On the contrary, if the humidity is less than 40%, the leaves of the plant will develop scorched edges and withered yellowing. At this time, water should be sprayed frequently, or a plastic cover should be added, or measures such as the deep-basin evaporation method should be used to increase air humidity. If foliage plants are in a dry environment for a long time, not only will the leaves lose their luster, but the growth vigor of the entire plant will also weaken, growing slowly or stagnating, until it withers and dies. Foliage plants bought home from flower shops often grow poorly, mostly because they are not adapted to the dry air indoors. Therefore, controlling humidity well is another key to the care and management of foliage plants.36.Why should air humidity be increased when growing flowers on a balcony？
All physiological function activities of flowers require the participation of water to proceed. Without water, the metabolic functions of flowers will stop, leading to death. Flowers absorb water through two pathways, namely from soil moisture and from air humidity. In hot seasons, high air humidity correspondingly lowers air temperature, which is beneficial to flower growth. Some flowers that like shade and moisture can only survive in relatively high air humidity. For example, orchids, Monstera deliciosa, ferns, and begonias require relative humidity between 80%-85% in summer, and in winter it must not be lower than 65%-75%; evergreen ornamental flowers such as hibiscus, white orchid, Lantana camara, jasmine, rubber tree, and poinsettia require relative humidity not lower than 70% in summer and not lower than 60% in winter; even drought-loving cacti or succulent plants must have relative humidity above 60% during the peak growth period in summer to grow well. Balconies are high up in buildings. In hot seasons, light is strong, causing the balcony floor, railings, walls, and other places to absorb more heat and release it slowly. As a result, the balcony temperature is high and air humidity is reduced; ordinarily, because buildings are high and winds are strong, air humidity is also not high. If balcony air humidity remains low for a long time, flower plants appear dim and lusterless, lacking vitality, and even new buds may dry at the tips, and leaves may have scorched edges and scorched spots, seriously affecting the growth and development of flowers and their flowering and fruiting. Therefore, growing flowers on a balcony requires increasing air humidity.Practical Complete Guide to Home Flower Growing (Part 2)
37.What soils are commonly used for potted flowers？
Various flowers and their different growth and development stages also have different soil requirements. The potting soil materials commonly used generally include the following types: Plain surface sandy soil. This is a fine surface sandy soil with a pure texture, little clay content, and smooth drainage. This soil is often used as sowing soil for general flowers, or as soil for cuttings of stems and buds of herbaceous flowers and softwood cuttings of woody flowers, and is also a main material for preparing culture soil. Peat soil. Also called turf soil, it is collected from peat bogs. It is formed after organic matter continuously accumulates under flooded and anaerobic conditions. Its organic matter content varies, with some reaching as high as 80%-90% or more. It contains large amounts of fiber and humic acid. It is soft in texture, has strong ability to adsorb fertilizer and retain water, and has good water and air permeability. Peat soil is acidic or neutral soil and contains organic matter. It is suitable as cutting soil for evergreen flowering trees that root slowly, or mixed half-and-half with plain surface sandy soil as sowing and cutting soil for general flowers. It can also be used to prepare culture soil. Garden soil. The surface weathered loam of gardens can be used as flowerbed soil or to prepare culture soil. Furnace ash soil. Furnace ash soil has strong drainage and air permeability and can be used to prepare culture soil. Sieved furnace ash residue can be placed at the bottom of the pot as a drainage layer. Mountain forest humus soil. It is formed by natural accumulation and fermentation decomposition of fallen branches and leaves, moss, and wind-blown sand in mountain forests. Humus soil can be made into culture soil with slight preparation. River mud. It is sediment soil from fish ponds and lotus ponds, containing large amounts of organic matter. After being dug out in autumn or winter, dried and weathered over winter, and mixed half-and-half with yellow clay, it can be used as cultivation soil for aquatic flowers such as lotus and water lilies. After river mud is dried in the sun, repeatedly turned and broken up, after one year it can be used to prepare culture soil. Mountain soil. This soil is commonly called orchid soil. It is natural humus soil produced in the mountainous areas of Zhejiang, formed by the decomposition of fallen leaves accumulated over many years. It is light in texture and both breathable and drainage-capable, while also retaining water and fertilizer. It is a good potting soil, tending acidic, suitable for cultivating acid-loving orchids, rhododendrons, camellias, etc., and can be used as soil for tree stump bonsai cultivation. Guangdong pond mud. It is fertile pond mud lumps from South China, the surface soil deposited at the bottom of fish ponds over many years. It is gray-black in color and contains decayed and decomposed remains and excrement of aquatic animals. It is rich in organic matter, has sufficient nutrients, and drains well. When ponds dry in winter, dig it out, dry it in the sun, crush it, and sieve it for later use. Large particles can be placed at the bottom of the pot. Because they are not easily broken apart, there is absolutely no risk of water stagnation. It is neutral or slightly acidic.
38.What are acidic soil and alkaline soil？
Soil acidity and alkalinity is a term for measuring how much acid and alkali are contained in soil. pH value is the symbol indicating the degree of acidity and alkalinity. Its corresponding values with acidity and alkalinity are shown below: pH value 3-4 5 6 7 8 9 10-11 Indicates strongly acidic acidic weakly acidic neutral weakly alkaline alkaline strongly alkaline. Soil with a pH value less than 7 is acidic soil, and soil with a pH value greater than 7 is alkaline soil. Table of adaptability of various flowers and trees to soil acidity and alkalinity: Acid-tolerant flowers and trees (pH4--5): rhododendron, cyclamen, gardenia, coleus, purple spiderwort, ferns, orchid family plants, etc. Flowers and trees suitable for weakly acidic soil (pH5--6): cyclamen, begonia, amaryllis, primrose, camellia, jasmine, Aglaia odorata, five-needle pine, lily, gladiolus, palm family, white orchid, gloxinia, etc. Flowers and trees adapted to neutral to slightly acidic soil (pH6--7): chrysanthemum, asparagus fern, Chinese rose, narcissus, hyacinth, osmanthus, fairy primrose, asparagus, poinsettia, fuchsia, taro, clivia, Magnolia liliiflora, Chaenomeles speciosa, etc. Flowers and trees suitable for neutral to slightly alkaline soil (pH7-8): rose, dianthus, geranium, cactus family, winter jasmine, boxwood, nandina, sweet pea, Prunus triloba, sabina, etc.
39.How can the acidity and alkalinity of potting soil be measured by a simple method?
The simplest method for measuring pH value is to buy some pH test paper, litmus paper, and a standard color comparison card from a chemical reagent store for measurement. When measuring, take a small spoonful of potting soil and place it in the bottom of a clean bowl. Add a small amount of distilled water until it just covers the test soil, and do not use too much. Then stir evenly and let it settle; this is the soil extract. Dip a bamboo stick into a little soil extract and place it on a small piece of test paper. If it turns red, it is acidic; if it turns yellow, it is alkaline. Compare the color shown on the test paper with the standard color comparison card, find the color card number closest in color, and that is the pH value of the measured potting soil.
Practical Complete Guide to Home Flower Growing (Part 2)
40.What role do the three major fertilizer elements play for potted flowers？
Among the various mineral elements required for plant growth and development, the ones needed in the largest amounts and most important are nitrogen, phosphorus, and potassium. Therefore, nitrogen, phosphorus, and potassium are called the three major fertilizer elements. Their roles are:Nitrogen fertilizer is also called leaf fertilizer.
It can make plants grow rapidly, with lush branches and leaves, and dark green leaf color. During the seedling stage and for foliage flowers, nitrogen fertilizer should be applied mainly. In the early stage of plant growth, that is, the vegetative growth period, nitrogen deficiency is even less acceptable. It is generally applied mostly from spring to early summer. If nitrogen fertilizer continues to be applied when plant growth and development have stopped (after summer), it will cause excessive growth of stems and leaves, making it difficult for the plant to finally mature and seriously affecting flowering and fruiting. Moreover, the stems and leaves are weak and easily damaged by pests and diseases. Therefore, before the plant enters the reproductive growth period (flower bud differentiation period), nitrogen fertilizer should be stopped. Human excrement and urine, soybean cake, ammonium sulfate, and urea are all nitrogen fertilizers.
Phosphorus fertilizer is also called fruit fertilizer.
It can promote flower bud differentiation and bud formation, make flowers brightly colored and strongly fragrant, and fruits large and good in quality, and can also promote robust plant growth. In the later stage of plant growth and development (reproductive growth period), applying it is most effective. Therefore, before flowering and after fruit set, more phosphorus fertilizer can be applied. Plants have the ability to store phosphorus fertilizer in their bodies and can regulate its use according to growth needs. Therefore, it can be applied sufficiently at one time in the base fertilizer. Plants have a certain limit to their ability to absorb phosphorus fertilizer. Calcium phosphate, potassium dihydrogen phosphate, and phosphate rock powder are all phosphorus fertilizers.
Potassium fertilizer is also called root fertilizer.
It can make stems and root systems grow robustly, making them less likely to lodge, and enhancing resistance to pests, diseases, and cold. It is indispensable in the early stage of plant development, during the seedling stage, shoot-drawing stage, and after transplanting seedlings. More potassium fertilizer can be applied. In the later stage of plant development, potassium fertilizer helps complete photosynthesis and plays an important role in the production of carbohydrates, especially for bulbous flowers that can store large amounts of carbohydrates, where its effect is even more significant. Therefore, throughout the entire plant growth process, potassium fertilizer is indispensable. For potted flowers kept indoors for a long time, because insufficient light weakens photosynthesis, a large amount of potassium fertilizer can be applied. Potassium fertilizer will also not cause fertilizer damage due to excessive application. Plant ash, potassium chloride, and potassium sulfate are all potassium fertilizers.
41.When potting soil lacks fertilizer, what adverse phenomena appear in plant growth？
When potting soil lacks fertilizer, the plant is short and weak, with few branches, abnormal leaves, and a poor appearance of vigorous growth. Because different fertilizer elements are lacking, the phenomena of poor growth are also different: when potting soil lacks nitrogen, the leaves are small, the leaf color is pale yellow, the lower leaves turn yellow first, and then gradually the whole plant loses green, with the lower leaves yellower and paler than the upper leaves; when potting soil lacks phosphorus, the leaves curl, the leaf color is dark green, the areas between veins of the lower leaves become yellow, appearing bronze-colored, the number of flowers is small, the root system is underdeveloped, and young buds sprout slowly; when potting soil lacks potassium, the edges of the lower leaves appear brown, and from the leaf tip downward the edges and middle of the lower leaves lose green and turn white, with various colored spots appearing between the veins; when potting soil lacks iron, scorched brown spots appear and dry up on both sides of the veins, inside the leaf margins, and at the leaf tips, sometimes expanding to form large areas of dryness, with only the larger veins remaining green.Practical Complete Guide to Home Flower Growing (Part 2)
42There are three methods for fertilizing potted flowers：
(1) Applying base fertilizerApplying base fertilizer to potted flowers is very important. If the base fertilizer is sufficient, less top dressing can be applied, and even chemical fertilizer alone can be used as top dressing, because repotting will be needed after 1-2 years, and it will not affect the quality of the potting soil.
Organic fertilizer made from fully fermented decomposed dried human excrement, barnyard manure, and household waste such as crushed bones, fish and poultry offal, and rotten vegetables is suitable as base fertilizer for potted flowers. The method of use is to mix 10% to 30% into the culture soil, keep it moist, and turn it frequently so that the fertilizer and soil are fully blended. Use it after one winter or 2-3 months in a high-temperature season. According to different compositions, it can be used separately for different flowers when potting, repotting, or changing pots. Hoof and horn materials and poultry feathers used as base fertilizer can be placed directly at the bottom of the pot when potting flowers. Oil meal fertilizers such as sesame paste residue and soybean cake, and bone meal used as base fertilizer, are used in the same way as manure fertilizer, with an amount of 3%-5% mixed into the culture soil.
For flowering trees not repotted that year, when the trees are dormant, you can also open a ring-shaped ditch along the edge of the pot, or symmetrically open short ditches, apply some of the above fermented organic fertilizer, and then cover with new culture soil. This can also replace applying base fertilizer.
Inorganic fertilizers (chemical fertilizers), such as phosphorus fertilizer, can use superphosphate and phosphate rock powder at 0.5%; nitrogen fertilizer can use ammonium sulfate at 0.2% and urea at 0.1%; potassium fertilizer can use potassium sulfate and potassium chloride at 0.1%. Mix into the culture soil two weeks beforehand as base fertilizer.
(2) Applying top dressing
During the growing season of flowering trees, applying dilute liquid fertilizer to supplement the insufficiency of the base fertilizer is called applying top dressing. For any fermented liquid such as urine, soybean cake water, fish intestine water, and rice-washing water, mix 1 part liquid with 10-20 times water, or use urea or potassium dihydrogen phosphate to make a 0.1%-0.2% aqueous solution, and apply 1-2 times per week, and once every half month after the Beginning of Autumn.
When applying top dressing, master the following: apply more nitrogen and potassium fertilizer during the vegetative growth period, and more phosphorus fertilizer during the flower bud formation period; loosen the soil the day before fertilization, and water the next morning after fertilization; apply after the beginning of spring, and do not apply after the Autumn Equinox; apply when buds appear, and do not apply when buds split; apply before rain and on sunny days, and do not apply after rain; apply in dry climates, and do not apply in the plum rain season; apply when the potting soil is dry, and do not apply when the potting soil is wet; apply more when the climate is suitable and growth is vigorous, and do not apply when the climate is hot and growth stagnates; also do not apply when newly planted, excessively growing, or dormant; apply thin fertilizer frequently, and do not apply concentrated fertilizer; for fertilizer-loving chrysanthemums and jasmine, you can apply more from light to concentrated; for barren-tolerant five-needle pine and other coniferous and cypress types, it is better to be light than concentrated and apply less; apply before and after flowering, and do not apply during the full flowering period; apply in the morning and evening, and do not apply at noon; apply more to strong seedlings and less to weak seedlings; do not let them go too hungry and do not let them be too full; do not apply if not decomposed and not diluted.
(3) Root-outside top dressing
Spraying a chemical fertilizer solution on the upper and lower surfaces of leaves to supplement the insufficiency of root fertilization is called root-outside top dressing. Because fertilizer components increase, the plant grows robustly, with many branches and green leaves, abundant and brilliant flowers, and enhanced disease resistance, but it cannot replace soil fertilization. Only inorganic fertilizers easily soluble in water, such as urea, ammonium sulfate, potassium chloride, superphosphate, and potassium dihydrogen phosphate, can be used, and they should be applied in the morning and evening on days with low temperature and high humidity. If the temperature is high, they dry easily and cannot be absorbed. A concentration of 0.1%-0.2% is unsuitable; too dilute gives low fertilizer effect, and too concentrated makes absorption difficult.
43.What issues should be noted when fertilizing potted flowers？
A flower proverb says: "Whether it lives or not depends on water; whether it grows or not depends on fertilizer." Reasonable fertilization is one of the key issues in the care of potted flowers. With proper fertilization, seedlings are strong and leaves lush, flowers are bright and fruits large; with improper fertilization, branches and leaves shrink, the plant is listless, and it may even die. When fertilizing household potted flowers, note the following points:(1) Fertilize according to different flowers and trees and different growth stages. A flower proverb says: "Clear orchid, turbid jasmine." This means orchids like light fertilizer, and jasmine likes concentrated fertilizer. Most flowers and trees like light fertilizer, and few like concentrated fertilizer. Although jasmine likes concentrated fertilizer, it is only during the dog days, and only with the cooperation of strong sunlight and heavy watering, that heavy fertilizer can be used. If concentrated fertilizer is applied as soon as it is brought out of the room, that would be terrible. Although chrysanthemums like heavy fertilizer, in the early growth stage, too much nitrogen fertilizer causes excessive growth and makes it difficult to form flower buds. Only during the process of flower bud formation can the amount and concentration of fertilization be gradually increased. Gardenias, rhododendrons, camellias, jasmine, and other acid-loving flowers and trees cannot be given alkaline fertilizers such as ammonia water and sodium nitrate. Bulbous flowers and flowering trees that need heavy pruning every year should be given more phosphorus and potassium fertilizer. Half a month before frost, overwintering fertilizer should be applied to improve cold resistance; before initial sprouting in early spring, bud-promoting fertilizer should be applied to make buds plump and sprout quickly; when spring shoots are about to mature, flower-promoting fertilizer should be applied to promote flower bud differentiation and plump buds; after flowering, apply thin nutritional fertilizer to restore tree vigor for flowering or fruiting again. During the full flowering period and early fruit set, fertilizer and water should be controlled, otherwise flowers and fruits easily drop. During the seedling stage, growth is rapid, so apply more nitrogen and potassium fertilizer. Before flowering and when buds appear, apply more phosphorus fertilizer.
(2) Loosen the soil before fertilizing, so that fertilizer water penetrates quickly and is easily absorbed. Also be careful not to let fertilizer water fall on leaves and buds, which would affect growth. Acidic fertilizers such as human excrement and urine, superphosphate, and ammonium carbonate cannot be mixed with alkaline fertilizers such as plant ash and ammonia water, otherwise they will neutralize and lose fertilizer effect. Alkaline potting soil should use acidic fertilizer, and acidic potting soil should use alkaline fertilizer. Be sure not to use a single fertilizer. Applying nitrogen fertilizer together with phosphorus and potassium can improve fertilizer effect; applying inorganic fertilizer together with organic fertilizer can prolong fertilizer effect, and can also prevent the potting soil from compacting and improve the potting soil's properties such as air permeability, water permeability, water retention, and fertilizer retention.
(3) When fertilizing on a balcony, pay attention to environmental hygiene, and also be careful not to dirty clothes hung out to dry on the balcony below, which would affect neighborly relations.
Practical Complete Guide to Home Flower Growing (Part 2)44.How to pot flower seedlings？
Potting refers to flowers beginning to be cultivated in pots, also called "entering the pot." Large seedlings of woody flowers are generally potted from early December to the end of March, when the flowering trees are dormant or just sprouting; otherwise it will affect normal growth and development and weaken tree vigor, so it will take a longer time to recover. For centralized cutting propagation, after rooting and leafing out, the seedlings should be divided and potted in time. Newly sown seedlings should preferably be potted when they become mature plants. For most perennial flowers, potting should be done when young buds just begin to sprout.
When potting bare-root seedlings (seedling roots without soil), delicate seedlings or those with severe root damage should first be planted in plain surface sandy soil for a period. In spring, pay attention to wind protection, and in summer, shade when necessary. After the root system becomes strong, repot and plant in culture soil. For robust bare-root seedlings, those with soil on the roots, and perennial flowers being potted, according to seedling vigor and habits, use culture soil for potting and appropriately add some base fertilizer.
Before potting, according to the size of the seedling and the speed of growth, choose an appropriate flowerpot, and be careful not to put a small seedling into a large pot. New pots should first be soaked thoroughly with water. Old pots often have water stains and debris and should be scrubbed clean. Cover the drainage hole with a tile piece or block it with weeds. For flowers afraid of waterlogging, according to the size of the flowerpot, place 1-4 cm thick residue sifted from the culture soil or somewhat coarse sand and stones at the bottom of the pot as a drainage layer. Ceramic and porcelain flowerpots need broken tile pieces as a drainage layer, and it should be thicker than that in clay pots. On top of the drainage layer, spread a layer of bottom soil, with thickness determined by the depth of the pot and the size of the plant. Generally when potting, fill soil to the original planting depth of the plant. Those with robust stems and fibrous roots can be planted deep; those with fleshy stems and roots must not be planted too deep. The upper part of the pot should leave a water space. The depth of the water space should be such that a normal full watering can penetrate to the bottom of the pot.
When potting bare-root seedlings, pile the bottom soil into a small mound in the center of the pot. With one hand, place the seedling upright and straight, and spread the fibrous roots evenly. With the other hand, add soil, and as you fill, gently lift the seedling so that the fibrous roots extend downward at a 45° angle. For flowers with relatively long fibrous roots, when potting, you can rotate the seedling so that the long roots coil evenly in the pot. After any flower is potted, be sure to firm the soil so that the potting soil is not empty below and solid above, or has cavities. Using hand pressing to compact it easily damages the roots. The soil used for potting should be moist, that is, it forms a clump when squeezed and breaks apart when rubbed. After potting, it should be placed in a wind-protected, shady, and humid place and not watered for the time being. In dry weather, water can be sprayed at any time to keep the seedling alive. Generally after 4-48 hours, water thoroughly again. This can not only prevent the fibrous roots from rotting and shrinking, but also promote rapid growth and recovery of new roots. After placing in a shady place for about 7 days, according to the habits of the flower seedling, move it to a sunny place or under a shade shed and transfer to normal care.
In conjunction with potting, the plant should be pruned. Overlong fibrous roots, diseased and dead branches, overly dense branches, and leaves should all be cut off. For excessively weak plants and flowering trees that bloom on current-year branches, cut back to 10 cm from the stem base to promote the growth and development of robust sprouting branches.
45Why do potted flowers need repotting? How to repot and change pots？
After 1-3 years of cultivation, the root mass of potted flowering trees fills the flowerpot, the nutrients in the potting soil are exhausted, and because of long-term watering, the potting soil becomes alkalized, the soil compacted, air permeability poor, and water retention poor. Even if top dressing is often applied, the flowering trees will not grow well. At the same time, as the flowering trees grow larger, the original flowerpot no longer suits their growth and development, so repotting and changing pots are necessary.Repotting and changing pots are routine work in flower growing. If potted flowers are not repotted or changed for many years, they will not grow well. Through repotting and changing pots, the flowerpot size can be made to match the seedling and nutritional conditions can be improved.
Repotting generally means moving flower seedlings that have grown for a period after potting into a pot one size larger, or moving flower seedlings originally potted bare-root in plain surface sandy soil into culture soil for planting. When repotting, the original soil ball is not disturbed, and there is no damage to the roots or aboveground parts, so the time for repotting is generally not restricted by season.
When repotting, the original potting soil must not be too wet or too dry. When removing the plant from the pot, use the index finger and middle finger of one hand to hold the base of the plant, with the palm close to the soil surface; use the other hand to support the bottom of the pot and turn it over, and gently tap the edge of the pot with the palm, and the whole ball can be removed. Then immediately remove the drainage layer at the bottom of the soil ball, slightly loosen the outer fibrous roots, and plant it in a larger pot.
Changing pots refers to potted flowers that have already been cultivated to form, in order to maintain a graceful plant shape and long-lasting vigorous growth, carried out before spring sprouting in combination with operations such as shaping and pruning. Changing pots is generally carried out before spring germination. For wintersweet, camellia, plum blossom, winter jasmine, etc. that bloom in early spring, pots can be changed after flowering. For potted flowers that grow quickly and bloom abundantly, such as jasmine, Chinese rose, hibiscus, and pomegranate, pots should be changed every year. For potted flowers that grow slowly, such as camellia, rhododendron, citrus types, and coniferous and cypress types, pots can be changed once every 2-3 years. Do not water for a few days before changing pots, so that the potting soil separates from the pot wall. Cut away 1/3 of the old soil from the original soil ball, and cut off some coiled roots and old roots. For potted flowers that have already been shaped, the original plant can be changed into the original pot. Generally, use a pot one size larger. After removing from the pot, cut off the tangled fibrous roots and rotten roots, remove part of the original soil, and replace with culture soil. Some flowers can also be divided when changing pots.
Practical Complete Guide to Home Flower Growing (Part 2)46What should be done if the plant root system has grown all through the pot？
To what state must potted foliage plants grow before they should be repotted? Observe whether the surface soil in the pot has bulged up, or whether roots have emerged from the bottom hole of the pot. This indicates that the root system in the pot has grown full, and at this time the pot should be turned over and the soil changed in time; otherwise the plant will weaken due to reasons such as nutritional deficiency or poor air permeability.
First, remove the plant from the flowerpot, cut off old roots and rotten roots, and also shake off some of the old soil attached to the root system. Find a flowerpot one size larger, place a few small stones at the bottom of the pot, first add a small amount of new soil, put the plant into the pot, then gradually add new soil until it is filled and compacted.
If you only want to change the soil and do not change the size of the flowerpot, shake off 1/3 of the old soil from the root system, and also cut off 1/3 of the old leaves. Only in this way can water absorption by the roots and water evaporation by the leaves maintain balance.
47.Why are some herbaceous flowers unsuitable for transplanting？
Herbaceous flowers unsuitable for transplanting are taproot-type flowers, whose main root extends straight down and has very few lateral roots. When transplanting, after the main root is cut off, lateral roots do not grow vigorously, and the ability to absorb nutrients decreases, so transplanting mostly does not easily survive or growth and development are poor. Plants such as morning glory, corn poppy, and California poppy belong to this category. Such herbaceous flowers are best cultivated by direct sowing. If transplanting is needed, they can be moved into small pots shortly after germination for cultivation, and after the seedlings grow, removed from the pots for transplanting, taking care not to damage the main root.Some herbaceous flowers are not tolerant of transplanting. For example, stock and wallflower cannot be transplanted many times or bare-root transplanted. When transplanting, try to lift large soil balls and do not let the balls break apart.
48.Why do some herbaceous flowers need several rounds of seedling transplanting？
Cultivated herbaceous flowers are usually raised in batches as seedlings, used to beautify the environment or arrange flowerbeds, and are required to be neat and beautiful. But often some herbaceous flowers planted into flowerbeds have a low survival rate or grow very weakly, failing to achieve the ideal beautifying effect. The main reason is that during the seedling-raising process, the measures of transplanting and hardening off were unfavorable. Some herbaceous flowers, such as Impatiens, China aster, Zinnia elegans, and marigold, easily grow tall and lodge. To cultivate short, sturdy, neat, drought-resistant, and waterlogging-tolerant flower seedlings, they must go through several rounds of seedling transplanting and hardening off during cultivation. When sown seedlings grow 2 true leaves, divide the seedlings bare-root in time, with a plant and row spacing of 10 cm. Water after planting, and water again 2-3 days later to help them recover. Then, when the surface soil is no longer sticky, loosen the soil in time to harden the seedlings. The hardening time depends on the weather, generally about 1 week. When the seedlings show wilting at noon, begin watering, and combine with fertilization. After fertilization, the seedlings visibly grow, then water once more. When the branches and leaves of the plants have already overlapped, transplant and divide the seedlings again. When transplanting seedlings, cut off the main root to promote lateral root proliferation. Cut soil balls 8-10 cm in diameter. After planting, similarly water twice to help them recover. After that, loosen the soil in time after each watering, and combine fertilization with watering. From sowing to final planting in the flowerbed, herbaceous flowers that have gone through 2-3 rounds of seedling transplanting grow sturdy, do not wilt after planting, and are neat and uniform. Herbaceous flowers grown at home should also not be planted too densely. During the seedling growth stage, there must also be a hardening-off process, and the soil should be loosened and fertilizer applied frequently so that they can become sturdy. Cuttings-propagated scarlet sage, chrysanthemum, etc. must also be cultivated in the same way to produce ideal flower seedlings.Practical Complete Guide to Home Flower Growing (Part 2)
49.What work does pruning of flowering trees include？
Pruning is one of the important means of growing flowering trees well. If all flowering trees are allowed to grow naturally, they will lose their due ornamental value. Pruning can not only create a good plant shape, but also regulate the reasonable distribution and supply of nutrients in the body, prevent excessive growth of branches and leaves, help flower bud differentiation and bud formation, and create good ventilation and light conditions and reduce the occurrence of pests and diseases.
50.How to prune and shape foliage plants？
Some large foliage plants, such as rubber tree, bamboo palm, coconut palm, Monstera deliciosa, and Schefflera octophylla, have relatively large plants. If pruned diligently, plant growth can be promoted, making them strong and beautiful. Topping can make plant leaves dense and the plant shape well-proportioned and prevent excessive growth; cutting off excess lateral buds can make the plant upright and tall.
Some smaller plants, such as Pilea cadierei, Peperomia, and aloe, need pruning to appear beautiful and lush. Therefore, before new buds begin to grow, cut off inferior branches to maintain a graceful shape.
To prevent foliage plants from growing excessively at will, a certain height must be determined, so the terminal buds of stems or branches must be cut frequently to inhibit growth and make the plant dwarfed or clustered. This is different from the pruning principles for general outdoor plants.
51.Does growing flowers indoors for a long time affect health？
Some people worry that keeping plants indoors for a long time may affect human health, but in fact this is unfounded anxiety. During the day, plants carry out photosynthesis, and the oxygen released is far more than what they themselves need for respiration. At night, although photosynthesis stops, their respiration is also extremely weak. Especially foliage plants, whose respiration is even weaker than that of flowering plants (flowering plants have the greatest respiration during the bud and flowering stages), and their oxygen requirement is even less.
Someone once did such an experiment: through respiration, 1 molecule of oxygen can produce 1 molecule of carbon dioxide, while the amount of oxygen needed to light 2 matches is equivalent to the respiration of two or three indoor plants in one night. It can be seen that the carbon dioxide exhaled by ornamental plants is negligible. From this point of view, indoor plants have no effect on human health. On the contrary, many indoor ornamental plants are also beneficial to people. For example, begonia, asparagus fern, and asparagus can not only absorb carbon dioxide gas, but also secrete bactericidal substances, which help prevent diseases such as colds, typhoid, and laryngitis. In addition, plants can also reduce indoor dust, clean the air, and increase negative oxygen ions, allowing people to live in a fresh and healthy environment.
Practical Complete Guide to Home Flower Growing (Part 2)
52.Why are most modern indoor ornamental plants mainly foliage plants？
People cannot be separated from nature. In today's world, in cities with towering buildings, people cannot own courtyard green spaces, and can only rely on indoor plants to bring the freshness of nature into their homes, and it is precisely foliage plants that occupy an absolute advantage among indoor plants. In a bedroom, study, or reception room, placing a few pots of ornamental plants not only adds color to the home, but also, after work or in a break from writing, glancing at the verdant and varied green "artworks" one has cultivated oneself makes fatigue vanish and brings joy and relaxation.
Foliage plants have leaves of different shapes and gorgeous, varied forms and can remain evergreen throughout the four seasons. Therefore, they can be enjoyed all year round without being restricted by season, especially for appreciating the posture and color of their leaves. Second, foliage plants are relatively shade-tolerant and prefer warm, humid environments. In terms of light and nutrients, their requirements are much lower than those of flowering and fruiting plants.
Some flowering plants also have the characteristics of foliage plants, for example: oleander, orchid, clivia, anthurium, bird of paradise, dwarf gloxinia, and so on.
Foliage plants are mostly ideal materials for indoor greening and decoration. In our country, foliage plants are still in a rising stage. Although they have already occupied major hotels and restaurants, they have not yet become widespread in family homes. It is believed that in the not-too-distant future, foliage plants will enter thousands of households.
53.Which foliage plants are suitable for home cultivation？
Some plants do not stand out for their flowers but win by their leaves. Their greatest characteristic is that they are not restricted by the blooming and fading of flowers and can be enjoyed at any time throughout the year. Among them are those appreciated for form, such as Monstera deliciosa, Fatsia japonica, rhapis palm, asparagus fern, and sword fern. There are also those appreciated for color, such as redwood, red maple, Excoecaria cochinchinensis, and purple spiderwort. There are also those with both form and color, such as coleus, purple velvet plant, and Dieffenbachia picta. There are also clivia, Chloranthus, and four-season epiphyllum that are enjoyed both for flowers and leaves. Placing a few pots in a family room gives a unique, beautiful, and novel pleasure. Below are several types suitable for the home and easy to cultivate:
54.Which flowers are suitable for hanging basket cultivation？
Hanging basket flowers are decorations for beautifying balconies and interiors. They can make full use of space and are most suitable for environments with small balconies and room areas. With flowerpots suspended indoors, outside the balcony, or at windows, the branches and leaves sway with the wind, giving a unique charm. Hanging basket devices must be firm. The height of the hanging basket should follow the principle of not hindering daily life. For the hanging rope, besides nylon rope, using the lock chain for hanging lamps is even more beautiful. For the care of hanging basket flowers, in addition to referring to the care of potted flowers, the direction of the hanging basket should also be changed frequently so that different parts can all receive sunlight. Sun-loving types cannot be hung indoors for a long time. Flowers suitable for hanging basket cultivation must have soft, drooping branches or flower scapes. For example: purple spiderwort, Sedum sarmentosum, Tradescantia zebrina, and Saxifraga stolonifera are all types that are easy to cultivate. The latter three are introduced below:
Practical Complete Guide to Home Flower Growing (Part 2)
55.What are the characteristics of climbing plants? Are they suitable for home cultivation？
In the wonderful natural world, plant shapes are diverse. Some plants have soft stems that cannot stand upright and need to twine around or attach to other objects to grow upward, so they are called climbing plants. Various climbing plants can be divided by their climbing methods into:
(1) Twining climbers, such as morning glory, cypress vine, Polygonum multiflorum, honeysuckle, and wisteria, which can twine around other objects and climb upward.
(2) Attachment climbers, such as grapes and loofah that rely on tendrils to climb; Boston ivy and American cotton that rely on suckers to climb; and Chinese trumpet creeper and ivy that rely on aerial roots to climb.
56.How to choose foliage plants？
When choosing foliage plants, decide according to the actual situation and requirements of the display room, hall, or living room, such as the size of the room, light, temperature, and the desired decorative effect. When first starting to grow them, you should buy varieties that are easy to cultivate. After accumulating rich experience, then choose those varieties that are relatively difficult to grow. For example, Pilea cadierei and red-edged ti can both quickly adapt to the environment and are easy to grow well; while Philodendron and Maranta plants require extra care.
When buying at the market, choose plants with bright, glossy leaf color and no yellow leaves or diseased spots. Also look at the bottom hole of the pot, and it is better to choose one with no roots growing out through the bottom hole. In addition, plants with a neat and beautiful shape, vigorous growth, and no excessively long branches are even better.
On the way home, the newly purchased plant should be wrapped well in a plastic bag to prevent wind damage or injury. Because of the bumpy journey, the shaking of the plant will cause the fibrous roots to loosen. After returning home, place the plant in a humid area without strong light and with good ventilation, keep the potting soil moist to encourage rooting, and after a few days place it in the position where it is to be displayed. This is called hardening-off treatment. After hardening-off treatment, the plant can adapt to the indoor growing environment and begin to grow.
57.How to choose flowerpots？
For potted flowering plants and trees, the material and volume of the flowerpot have a great influence on their growth, so choosing a reasonable flowerpot is very important. An ideal flowerpot should have: lightweight material for easy carrying; durability, not easily broken; colors, shapes, thickness, and sizes that suit the needs of flower and tree growth, with a variety of specifications and models available; and a low price, among other conditions.
The Complete Practical Guide to Home Flower Growing (Middle Volume) 58.What safety issues should be noted when installing a balcony flower rack？Balcony flower racks are generally installed on the balcony railing. In order to use space, they also extend outward beyond the balcony, so only the side resting on the balcony railing is a load-bearing point, while the other side extending beyond the outer side of the balcony is supported by galvanized wire hanging. For safety, it is best to add support beneath the part of the flower rack extending beyond the outer side of the balcony, making it more sturdy, safe, and reliable.
The three sides of the flower rack extending beyond the balcony should be fitted with steel bars or wooden boards to form a barrier about 15 cm high, to prevent flowerpots from falling. Some flower racks on balconies do not have this barrier. When clothes are being dried on the balcony or other household chores are being done, flowerpots may accidentally be knocked off, and cases of people being injured have been heard of. This must draw the attention of balcony flower growers.
59.How to set up a shade shed for growing flowers on a balcony？
Growing flowers also requires the setup of a shade shed. The balcony area is small. If only a small number of strongly sun-loving flowers are grown, such as crape myrtle, jasmine, peach blossoms, citrus plants, succulents and cacti, as well as annual and biennial herbaceous flowers, a shade shed may not be needed. If some shade-loving flowers are also to be grown, then a shade shed is needed; moreover, in the scorching summer, some sun-loving flowers such as wintersweet, osmanthus, gardenia, and Chinese hibiscus also need appropriate shading; there are also some sun-loving flowers such as Chinese roses and superior varieties among cacti that also need shading at noon.The shade shed can be installed near the window side close to the balcony. Installing a flower rack below the window means that although not many potted flowers can be placed, planting and maintenance operations are very convenient. The shade shed can also serve as a sun-blocking curtain, helping to prevent heat and lower indoor temperatures. If a shade shed is set up on the balcony flower rack, it will hinder drying clothes and bedding on the balcony and also affect other household activities there. For this reason, it is better to install the shade shed on the window beside the balcony. In this way, sun-loving flowers are grown exclusively on the balcony flower rack, and shade-loving flowers are grown exclusively under the window shade shed, without interfering with each other.
The shade shed does not need bamboo, reed stems, or other special materials for construction. It can also be made using the trellis for growing climbing flowers and trees, which not only provides shade but also beautifies the balcony and window. The balcony shade shed should not be too high. Apart from the shade shed on the window, which must be installed according to the window height, the shade shed on the flower rack is suitable at 1.2 m or below. Balcony potted flowers should all be kept at around 80 cm; too high blocks the wind and is not easy to set up, while too low makes maintenance operations inconvenient. In addition to shading the top of the shade shed, the side facing the west sun should also be shaded, but ventilation must also be considered. It is better to plant small vines and climbing plants with smaller leaves in the shade shed, because the shade shed area is not large. For this purpose, honeysuckle and banksia rose are most ideal. Although Chinese trumpet creeper is a large vine, its leaves are relatively small, and the gaps through which sunlight passes are also small, so its shading effect is better than that of large-leaved grapes. If a higher degree of shade is desired, some herbaceous climbing plants can also be planted, such as cypress vine, morning glory, and hyacinth bean, which produce an even better decorative effect.
60.Where is a good position to place large foliage plants indoors？
Plants growing above 1.2 m are generally called large foliage plants, and most of them are woody types.Common large foliage plants include: sago palm, Norfolk Island pine, rubber tree, Swiss cheese plant, heavenly bamboo, croton, Japanese aralia, oleander, broadleaf lady palm, ti plant, dragon blood tree, pothos trained into a totem pole, and English ivy, among others. These plants have elegant forms, are full of presence, cover a large decorative area, and are suitable for placement in relatively large rooms. Small rooms are not suitable for arranging large plants, because in that way the plants not only take up a great deal of space but also fail to produce a decorative effect, making the room appear even more crowded.
Large foliage plants should be placed on the floor, or beside a writing desk, or in a certain corner, or at the bend of a corner sofa. When placing them, it is best to put a more attractive pot over the outside of the clay pot, such as a porcelain pot, ceramic pot, plastic pot, or even a fiberglass-reinforced plastic pot. The color of the outer pot should harmonize with the indoor furniture.
Of course, when placing these foliage plants, be sure to meet their ecological conditions. If the indoor environment does not provide the conditions for plant growth, but for the sake of some happy occasion or welcoming guests it is necessary to create atmosphere and produce an elegant, peaceful, and comfortable environment, then it is best to keep these large plants in place for only one or two days, and then remove them. Many flower businesses have rental and placement services. They rent out flowers, which for many customers is both economical and practical.
Recommended reading:The Complete Practical Guide to Home Flower Growing (First Volume)
The Complete Guide to Orchid Cultivation and Growing Techniques
"Three parts planting, seven parts care" is the ancients' experience in growing orchids. The quality of care determines whether orchids thrive and whether they can bloom, so it makes sense that predecessors attached great importance to this. The following specifically introduces methods for caring for and managing orchids.I. Location
The location where orchids are placed is very important, as it directly affects the growth and development of orchids. Orchids are generally placed outdoors in spring, summer, and autumn (in summer, placed in a shaded outdoor spot), and indoors in winter. Outdoors, it is best to have open surroundings and moist air. Indoors, there should be ample light, preferably facing south. This is favorable for orchid growth. Orchid pots are best placed on wooden racks or tables, not on the ground.
II. Shading
Orchids mostly belong to semi-shade plants, and most species fear direct sunlight and need appropriate shading. In early to mid-April, orchids can receive more sunlight to promote growth. After late April, they should be appropriately shaded. Among summer orchids and autumn orchids, varieties with upright leaves are best placed on the south side of a shaded area so that they receive appropriately more sunlight; for autumn orchids and spring orchids with drooping leaves, two hours of light per day is best. From the beginning of June to September, shading should be started earlier each day. If reed curtains are used, dense curtains or two layers of sparse curtains can be used. After October, the weather turns cooler and sunlight is weaker, so shading can be delayed, but around noon, attention must still be paid to providing shade.
III. Rain Protection
Orchids can be exposed to light rain, but must be protected from plum rain, showers, or continuous rain. During the plum rain season, rain protection work must be especially well done. From late June to mid-September, there are often showers. If the rain is short in duration and light in amount, more water should be given in the evening to let the heat inside the pot escape; otherwise, the orchids will be damaged, or even have root rot and die. If a shower is followed by sunshine, shade must be provided in time to prevent heat rising from the ground from affecting orchid growth. In rainy seasons, which coincide with the stage when orchids are sending out leaf buds, if the potting soil is too wet, leaf buds may grow poorly or diseases may be induced. At this time, a small amount of plant ash can be scattered to regulate the moisture of the potting soil.
IV. Watering
There is a saying among flower growers: "dry orchids, wet chrysanthemums." This saying has some truth. Generally speaking, orchids are best kept with eight parts dry and two parts wet. If too wet, the flowers are prone to root rot and death. The principle of watering should be: water when dry, stop when wet, and appropriately lean toward dry. In specific practice, generally note: during the growth period (from May to the end of June), water appropriately more; during the leaf bud emergence period (about March to April) and the flowering period (about March to April), water appropriately less; during the dormant period (winter), water even less or not at all. If the flowerpot is large and the orchid plant is small, water less; if the pot is small and the plant is large, water more. In hot and dry weather, water appropriately more; in cool and humid conditions (such as the plum rain season), water less or not at all. Newly dug orchids from the mountains, if their root systems are sparse or many roots are broken, should be watered less, keeping the potting soil a bit dry, so that root rot does not occur and new leaves are encouraged to emerge. The ancients' experience that "do not let them dry in autumn, do not let them stay wet in winter" is a very good summary of how to water spring orchids and summer orchids. However, in some northern regions, because the climate in winter and early spring is too dry, orchids should not be allowed to become overly dry either. Watering time: in summer and autumn, it is best to water after sunset so that the orchid leaf surfaces dry before nightfall; watering in the early morning is also acceptable. In winter and spring, it is best to water around sunrise. Do not suddenly use cold water to irrigate after scorching sun exposure, to avoid lowering soil temperature, affecting root water uptake, and disturbing physiological balance. The amount of water should not be too large, so as to help suppress the occurrence of disease.
Watering method: water should be poured in from the edge of the pot, and must not be poured into the flower buds, to avoid causing rot.
Predecessors had very good summarized experience on watering orchids. For example, in "Record of Orchid Cultivation in the Capital" by Yu Zhao, different watering methods were proposed according to the twenty-four solar terms within a year. Excerpts are given below for reference. But two points should be noted: first, "Record of Orchid Cultivation in the Capital" uses Beijing's climate as the standard; second, the months in the text refer to the lunar calendar rather than the Gregorian calendar. For example, "the first month" is actually February in the Gregorian calendar.
1. Beginning of Spring and Rain Water: spring orchids have already produced flowers, so the soil should not be too dry; moisten it slightly along the edge of the pot; if the soil in the autumn orchid pot has not dried to the bottom, do not water.
2. Awakening of Insects: when the soil in a spring orchid pot is dry to half the pot (dry on top, firm below), it can be moistened, but not too much. The same as above for autumn orchids.
3. Spring Equinox: spring orchids have finished flowering and should avoid dampness; when the pot is half dry, it can be moistened.
4. Pure Brightness and Grain Rain: do not let the potting soil become too dry; moisten with water every 5 days.
5. Beginning of Summer: orchids begin to be brought out of the room; it is suitable to water thoroughly once.
6. Grain Full: do not let the potting soil become too dry or too wet. If spots appear on the leaves, it is too wet; if the tips of new buds wither, it is too dry. Water 1 sheng every 4 days (about a dry teacup), so that the lower two-thirds of the potting soil is moistened from the bottom upward.
7. Grain in Ear: the climate is dry, so even more attention should be paid to avoiding excessive dryness or wetness.
8. Summer Solstice: the potting soil must not be too dry. If heavy rain occurs, it can only be endured for one day. If there are successive cloudy and rainy days, the pot should be moved to a ventilated place.
9. Minor Heat: at this time the air is too humid, and the potting soil must not be too wet. The pot should be placed in a ventilated place. If it is hot and dry with little rain, water 1 sheng every 2 days. After heavy rain or one heavy wetting, it must be allowed to dry until two-thirds of the potting soil is dry; otherwise, do not water again.
10. Major Heat: the potting soil easily dries all the way through, so note that only one heavy rain or one heavy wetting per day is suitable.
11. Beginning of Autumn: orchids need water at this time; water 2 sheng every 3 days, and they should also be protected from wind.
12. End of Heat: water once every 5 days. Except during successive hazy rainy days, they can be allowed to receive rain and dew.
13. White Dew: autumn orchids need frequent watering even more than spring orchids, but after becoming wet they must dry greatly before they can be wetted again.
14. Autumn Equinox: if autumn orchids have already produced flowers, watering should be slightly less; if they have not produced flowers, watering should be slightly increased.
15. Cold Dew: autumn orchids should be watered thoroughly; spring orchids should not be watered thoroughly but only moistened.
16. Frost Descent: orchids should be brought indoors, and the watering time should be changed to midday. After watering, they need to be placed in the midday sun for 1-2 hours.
17. Beginning of Winter: only moistening with water is suitable, about half a sheng every 5 days.
18. Minor Snow: the flower room should avoid warmth and should not be too humid. If too humid, it can cause root rot, spotted leaves, and even withering. If the potting soil has not dried to the bottom, only slightly moisten the surface soil.
19. Major Snow: autumn orchids do not need water; spring orchids should be slightly moistened.
20. Winter Solstice: neither should be irrigated.
21. Minor Cold: watering should be avoided for both.
22. Major Cold: autumn orchids still do not need water; spring orchids can be slightly moistened with water.
V. Fertilization
Whether to fertilize orchids should be decided according to their growth condition. Those growing luxuriantly and without disease can be fertilized; those growing poorly should not be fertilized or should be fertilized only lightly. Newly dug orchids from the mountains must absolutely not be fertilized before new roots have developed. They need 1-2 years of cultivation, and only when the new roots are vigorous can they be fertilized; otherwise, they are prone to withering and dying.
Generally speaking, in June-July, when orchid leaf buds have extended to about 1.5 cm, 1-2 applications of thin, fully decomposed liquid fertilizer may be given (chemical fertilizers are not suitable), but fertilization is not suitable in high-temperature seasons. In August-September, apply 1-2 more applications of fully decomposed thin liquid fertilizer. For plain-heart orchid varieties, 1-2 applications of plant ash extract can be given, with very good results. Fertilization is best done in the evening, and then once more with clear water on the following morning.
A relatively simple way to judge whether orchids need fertilization is to look at the depth of leaf color. If the leaves appear yellow and thin, there is a lack of fertilizer, and topdressing should be applied; if the leaves appear dark and the leaf tips are scorched, there has been too much fertilization, and fertilization should be stopped.
For fertilizer, the various methods introduced above can be used to make fertilizer at home. When applying these fertilizers, they need to be diluted with 8-9 times water, and must not be too concentrated. When fertilizing, apply it to the root zone of the plant, and absolutely do not apply it to the leaf surface. The main fertilization times and dates for orchids: times, dates, categories, first time, second time, third time, fourth time, remarks.
Spring orchid types: late June, mid-July, mid-August, early September. The fourth application should be especially thin.
Summer orchid types: late June, mid-July, mid-August, early September. The fourth application should be especially thin.
Autumn orchid types: early June, late June, late July, mid-August. The fourth application should be especially thin.
VI. Pruning
During orchid cultivation, pruning must be carried out continuously. When old leaves turn yellow and withered, they should be cut off in time to improve ventilation. Some leaves whose tips have dried should also be cut off. In particular, leaves damaged by pests and diseases must be removed in time to prevent transmission. When cutting off leaves with viral disease, the scissors used should not then be used to cut healthy leaves, to prevent virus transmission. If the same pair of scissors is used, it must be disinfected. After the flower buds of precious orchid varieties emerge from the soil, if there are too many flower buds, the strong buds should be retained and the remaining thin, small flower buds removed. It is suitable to keep 1-2 flower buds per pot. If there are too many flower buds, not only will the current year's flowers not open well, but too much of the mother plant's nutrients will also be consumed, affecting flowering the following year. Generally, orchids may not need to have their flower buds removed. The flowers of spring orchids bloom for about half a month, and then the flowers should be cut off; for summer orchid flowers, when the last flower on the inflorescence has been open for one week, the inflorescence should also be cut off. Precious varieties should not be allowed to be pollinated and set seed; otherwise, flowering the next year will be affected. If they are used for hybrid breeding, then they need additional careful cultivation so that the fruit becomes full and ripe.
VII. Cold Protection
Autumn orchids should have cold protection work done early. If the temperature is 2-3°C, they can be moved indoors. Cold orchids grow in the south and need even earlier cold protection. Spring and summer orchids have relatively strong cold resistance, but if freezing occurs, they must also be moved indoors in time. If room temperature can be maintained at 1-2°C, they can overwinter. If a severe cold wave strikes and room temperature drops below zero, heating must be carried out in time; generally, keeping the room from freezing is enough. Indoors, autumn orchids should be placed on the south-facing side, and spring and summer orchids on the other side. Around noon, windows facing south and southeast should be opened for ventilation (autumn orchids should not have windows opened on cloudy days at 1-2°C, to prevent cold wind from blowing in and freezing the leaves). Autumn orchids prefer to be somewhat dry in winter, while the potting soil of the other orchids should be kept moist.
VIII. Flower Removal
For orchids that grow poorly, with few leaves per clump or poor roots, flower removal should be carried out. For better varieties, spring orchids may appropriately have 1-2 flower buds removed; for summer orchids, when the flower buds have extended, keep 1-2 flower buds and remove the rest. In this way, the flowers can remain open longer, more new leaves can be sent out, and old leaves are less likely to wither and die. Precious spring orchids should have their flowers removed after 3-5 days of blooming, so that leaf buds grow vigorously; for summer orchids, when the topmost flower has opened, it can also be cut off at a distance of several cm from the pot surface.
IX. Flood Prevention
If the cultivation site has open surroundings and higher terrain, then in summer when strong winds or typhoons pass through, wind protection work must be done well, to prevent the leaves of summer orchids or cold orchids from being broken and damaged.
X. Misting
In dry seasons, mist every evening on the balcony where potted flowers are placed, mainly to make the ground moist and increase air humidity. The pot surface of orchids should also be misted. When misting, spray upward so that the mist droplets fall finely and evenly, moistening the leaf surfaces. This can promote good orchid growth and give the leaves a glossy appearance.
XII. Pest and Disease Control
Sterilization treatment should be carried out (exposure under the scorching sun is sufficient) to prevent disease occurrence. Orchids are most prone to southern blight in rainy and high-temperature seasons. It can be prevented by spraying with 800-times thiophanate-methyl solution or Bordeaux mixture. If the disease is severe, thiophanate-methyl at 500-750 times dilution can be used, sprayed once every 7-10 days. Among insect pests, scale insects occur most frequently. This insect attaches to the base of the leaves. If scale insects are found, they should be removed in time. To avoid scale insect infestation, starting in April, "1059" at 2000 times dilution can be used for control. In order to suppress the occurrence of orchid diseases, in addition to properly controlling the dryness and wetness of the potting soil at ordinary times, clay pots should also be used as much as possible and glazed pots used less when selecting flowerpots. In particular, newly dug orchids from the mountains that grow poorly must be planted in clay pots. Doing so makes the potting soil dry easily, which can promote orchid growth and reduce disease occurrence.
How should orchids be grown well?
1. Potting soil requirements: a neutral to slightly acidic soil containing abundant humus, loose, and well drained is best. The pH value is generally about 5.5 to 6.5. In Sichuan, Emei Xiantu and "Xinghong Brand" refined orchid growing medium are often used, and more commonly "bamboo root soil" and leaf mold from broad-leaved forests in mountainous areas are used to cultivate orchids.
2. Placement site: orchids can be cultivated outdoors and on balconies in spring, summer, and autumn. Choose a place with good ventilation, moist air, and no environmental pollution. Being near ponds or riversides is of course good, but at least there should be tall trees or bamboo groves and shade netting to reduce sunlight exposure and lower temperature. Orchid pots are best placed on wooden racks (or steel racks). If placed on the ground, bricks should be used underneath. Home balconies can also use small galvanized iron sheet water troughs to store water and place bricks on top for cultivation, increasing humidity.
3. Appropriate shading: orchids mostly belong to semi-shade plants, and most species fear direct sunlight and need appropriate shading. In early to mid-April, orchids can have the net removed and windows opened, receiving more sunlight to promote growth. In May, aside from the midday sun, they can receive 6 hours of light; starting in June, shade all day; after October, aside from midday, they can be fully exposed for cultivation. Remember the saying: "More shade gives good leaves, more sun gives good flowers."
4. Reasonable fertilization: orchids are inherently "vegetarian," and fertilization should be determined according to the selected potting soil and growth condition. Those growing luxuriantly and without disease can be fertilized; those growing poorly should not be fertilized or should be fertilized only lightly. Newly planted orchids in pots whose roots have not fully developed need 1-2 years before they can be fertilized. Generally, in June-July, when orchid leaf buds have extended to about 1.5 cm, apply fully decomposed liquid fertilizer once every three weeks (a thin concentration of 10% is suitable). Avoid chemical fertilizers. In high-temperature seasons, fertilization is not suitable. In August-September, apply diluted liquid fertilizer once every two to three weeks. Each fertilization of orchids is best done in the evening, and clear water should be given in the morning, called "return water."
5. Appropriate watering: rainwater and spring water are best for watering orchids. Tap water or rice-washing water should be left overnight before use. When watering, pour from the edge of the pot, and do not pour into the flower buds. The amount of water should be determined according to temperature, the dryness and wetness of the potting soil, and the growth condition of the orchid. Water more when there are many leaves, and less when the leaves are fine. In April-May, when new buds have not yet emerged from the soil, the potting soil should be somewhat dry; if too wet, new buds easily rot. June-September is the growth period for new orchid buds, and the amount of water should be increased. On sunny days, water once each morning or evening, and absolutely avoid watering under the scorching midday sun. In autumn, reduce the amount of water as appropriate, and leaf-surface misting can be used, keeping the potting soil moist as the better approach. In winter, the amount of water should be controlled even more, keeping it at "eight parts dry, two parts wet" as suitable.
6. Evening misting: orchids originally grow in a humid-air environment, so in dry seasons, in addition to shading, evening misting is also necessary to increase air humidity and lower temperature. Water can also be poured onto the ground (table surface) where orchid pots are placed. "One cold and one hot" can further stimulate orchid growth.
7. Wind and rain protection: "February ghost wind" causing old leaves to yellow and fall is a normal phenomenon, and dead branches and withered leaves can be cut away. Orchids can be exposed to light rain, but must be protected from plum rain, torrential rain, or continuous rain; otherwise, the heart and leaves easily rot. In rainy seasons, a small amount of plant ash may be scattered appropriately.
8. Pruning and flower removal: during orchid cultivation, withered, yellow, broken, and diseased leaves should always be cut away to improve ventilation. For precious orchids, if there are too many flower buds, keep only the strong buds, and 1-2 flower buds per pot is suitable. Spring orchids should have their flowers removed after half a month of blooming; precious orchids should be removed after 7 days, so that the leaf buds of spring orchids grow vigorously and bloom better the following year. For summer orchids, when the last flower on the inflorescence has been open for one week, cut it off 3 cm from the pot surface.
9. Cold protection and warmth: because orchid varieties differ, their places of origin vary, and their cold resistance is also different, so the time for bringing them indoors in winter and their indoor placement positions are also different. Cold orchids, autumn orchids, and Chinese New Year orchids grow in the south, and are suitable to be brought indoors (or have windows closed and netting put up) when the temperature is 5°C, and placed in a south-facing sunny spot as much as possible. Spring and summer orchids have strong cold resistance, and can be brought indoors only when the temperature reaches 0°C, and placed on the northeast side. On sunny, windless days around noon, windows facing south or southeast should be opened, and netting pulled open for ventilation. Autumn orchids should not have windows opened on sunny days at 1-2°C. Of course, where there is a greenhouse, electric lighting can be used for heating.
10. Disease and pest control: potting soil should generally undergo sterilization treatment (exposure under the scorching sun is also acceptable), to prevent disease occurrence. Orchids are most prone to southern blight in rainy, high-temperature seasons. For a small amount, a damp cloth can be used to wipe it away. If there are many pots, 500-800 times Bordeaux mixture or thiophanate-methyl can be used, sprayed once every 7-10 days. Among insect pests, scale insects (commonly known as "orchid lice") occur frequently. During the hatching period, use 1% omethoate and 25% phosmet emulsifiable concentrate at 1000 times dilution, sprayed once a week. To treat the symptoms one must also treat the root cause: pots should be spaced appropriately, placed high and low, and ventilation increased, so as to reduce disease occurrence.
(II) Ecological Habits of Orchid Cultivation
Orchids originated in our country. They like warmth and humidity, and especially ideal conditions are warm winters and cool summers. High temperature and dryness must be avoided. In winter, it is best if they do not freeze, and maintaining 3°C-7°C is most suitable; in summer, 25°C-28°C is suitable. In their natural distribution, orchid production areas are near streams and ravines, receive rain and dew year-round, and require annual rainfall of more than 1000 mm. They require deep upper soil, rich in humus, dark brown, loose and fertile, with good water permeability and water retention, and slightly acidic soil, pH 5-PH 6.5. Waterlogging must be avoided.
Orchids like shade and require short sunlight duration. In their natural distribution, it is shown that spring orchids require tree shade density of 0.7-0.95; cymbidium faberi requires 0.5-0.8, and its light duration is slightly longer than that of spring orchids; cymbidium ensifolium, cymbidium sinense, and cymbidium kanran also require a high degree of shade. Cymbidium plants have a dormant habit in their places of origin, which depends on the rainy season and dry season. Usually the dry season is in winter, which is the dormant period for orchids, and the rainy season is in spring and summer, which is the growth period for orchids, when they can continuously send up buds and bloom.
(III) Propagation Methods for Orchid Cultivation Orchids are commonly propagated by division, sowing, and tissue culture.
1. Division: This can be done in both spring and autumn, generally once every three years. Any plant that grows robustly and has densely clustered pseudobulbs can be divided. After division, each clump should retain at least 5 connected pseudobulbs. Before division, reduce irrigation so that the potting soil is relatively dry. When potting after division, first cover the drainage hole at the bottom of the pot with broken tile pieces, then spread coarse gravel to occupy 1/5 to 1/4 of the pot depth, then add coarse-grained soil and a small amount of fine soil, and then plant with sandy loam rich in humus. The planting depth should be such that the pseudobulbs are just buried in the soil. Leave a 2 cm rim at the edge of the pot, spread Selaginella uncinata or fine gravel on top, and finally water thoroughly. Place in a shaded area for 10-15 days, keep the soil moist, then gradually reduce watering and carry out normal maintenance.
2. Propagation by sowing: orchid seeds are extremely fine, and inside the seed there is only one incompletely developed embryo, with very low germination capacity. In addition, the seed coat does not easily absorb water, so sowing by conventional methods cannot germinate. Therefore, orchid mycorrhizal fungi or artificial culture medium are needed to supply nutrients for germination. For sowing, it is best to select fruit that has not yet split. After sterilizing the surface with 75% alcohol, take out the seeds, soak them in 10% sodium hypochlorite for 5-10 minutes, take them out, rinse them 3 times with sterile water, and then sow them in culture bottles containing culture medium. Then place them in a dark culture room, maintaining the temperature at about 25°C. After they begin to sprout, move them into the light, and they can form protocorms. From sowing to transplanting takes half a year to one year. Tissue culture has already been successful, and where conditions permit, this method can be used for propagation.
(IV) Cultivation Techniques for Orchids
1. Site selection: the surroundings should be open, well ventilated, close to water, with moist air, and free of coal smoke pollution. On the southwest side of the site, evergreen broad-leaved trees can be planted, with a canopy density of about 0.7. This can reduce afternoon sunlight exposure and regulate humidity and temperature.
2. Watering: rainwater or spring water is suitable; water containing salt and alkali should not be used. If tap water is used, it should be left standing for several days before use. Watering should be determined according to temperature conditions. In spring, the amount of watering should be less; in summer, more. The plum rain season coincides with orchids sending out leaf buds, and the potting soil should be somewhat dry. After autumn, the weather turns cooler, and the amount of watering should be reduced as appropriate, keeping it moist. In winter indoors, it should be dry, reducing watering frequency, and it is suitable to water at noon. Orchids can be exposed to light rain, but continuous rain or torrential rain easily causes heart and leaf rot, so attention must be paid to rain protection.
3. Fertilization: for growing orchids, cake fertilizer is suitable. Mix 4 parts plant ash, 10 parts soybean cake, and 10 parts bone meal evenly, place in a jar, add water several times until the soybean cake is soaked through, then cover and seal. After one year of decomposition, make it into dry granules. When using, place it on the pot surface. If full manure is used, it should also be decomposed for one year, then diluted with water, filtered, and used. Generally, fertilization starts in May and stops at the Beginning of Autumn, with the principle of thin fertilizer applied frequently. Fertilization should be done in the evening, and then once with clear water the next morning.
4. Shading and cold protection: except in early spring and winter, they should be placed under open-air sheds. The shade shed requires good ventilation. When orchids have just been brought out in March-April, they can receive more sun; afterward, shading time gradually increases. In winter, orchids must be moved indoors for cold protection, and maintaining room temperature at 1°C-2°C is sufficient. In addition, after orchids are brought out in spring and before they are brought indoors in autumn, attention must also be paid to frost protection.
5. Pest and disease control: the main pests and diseases of orchids are:
(1) Southern blight: mostly occurs in the plum rain season. Attention should be paid to ventilation and light transmission and good drainage of the potting soil for prevention. After onset, remove the infected potting soil and sprinkle pentachloronitrobenzene powder or lime on it.
(2) Anthracnose: occurs year-round, and is more rampant in high-temperature and rainy seasons. In addition to improving environmental conditions, control methods include first spraying with 50% methyl thiophanate wettable powder at 800-1500 times dilution during the onset period, once every 7-10 days, and then supplementing with 1% equal-amount Bordeaux mixture, once every half month.
(3) Scale insects: they reproduce fastest under high temperature, high humidity, and poor air circulation. Use conventional methods for control.
In summary, to grow orchids well, one must master their natural growth environment conditions, adopt reasonable measures, and strengthen maintenance and management. According to "Orchid Cultivation Formula": "Do not bring them out in spring, do not expose them to sun in summer, do not let them dry in autumn, do not let them stay wet in winter." This is a summary of our country's experience in growing orchids.
A Brief Discussion on the Reasonable Use of Medicines for Orchids
Fungicides are agents for preventing and controlling crop diseases. In our usual prevention and control of orchid diseases, we must choose according to the different properties and modes of action of different categories of fungicides. One category is protective fungicides, whose role is to treat plants or the environment in which plants are located before pathogens invade. They need to be used before plants come into contact with pathogens or before disease occurs in order to be effective, such as Bordeaux mixture, lime sulfur mixture, mancozeb, zineb, and so on. There is also another category, therapeutic fungicides. We often come into contact with this type of fungicide. Its characteristic is that it is systemic. The use of this type of fungicide is when the pathogen has already invaded the plant body or the plant has already become diseased; at this time it is applied to reduce or eliminate plant disease. Applying the medicine in the early stage of plant disease gives better results.
The initial and peak stages of disease for different pathogens also differ, and are greatly affected by the external environment, especially the growth and development status of the infected crop and temperature and humidity. (Therefore, we must grow orchid seedlings strong.) When preventing and controlling diseases, it is better if everyone can be familiar with the living habits and epidemic patterns of the pathogenic organisms, and can carry out disease control according to different seasons and temperature environments. This plays a huge role in the effective exertion of pesticide efficacy. The crop diseases caused by various pathogens are different, and the disease symptoms are also clearly different. Therefore, when choosing fungicide medicines, symptomatic treatment is required. Moreover, the efficacy should be significant and lasting. One should not blindly pursue high efficiency, broad spectrum, or even "universal" medicines, as if no matter what the disease, one medicine can handle it. This is definitely not acceptable. When using medicines, attention should be paid to preventing the development of pathogen resistance, that is, the same fungicide cannot be used continuously, nor can the same category of fungicide be used several times in succession during one growth period. In particular, the number of uses of systemic agents should be limited. For example, in production, systemic agents can be used in combination or rotation with chlorothalonil, mancozeb, and so on.
In our daily use of medicines, we should adopt corresponding control measures according to the patterns of pathogen infection. When using fungicides to spray directly on orchid plants, attention should be paid to the influence of natural conditions, to prevent loss of efficacy or phytotoxicity. When temperature and humidity are relatively high, the concentration of the pesticide used can be appropriately reduced; for pesticides that easily decompose or volatilize under strong light, they should be applied on cloudy days or in the evening. Different pesticides all have certain scope of use. Only by understanding them deeply and mastering their usage characteristics can one correctly select pesticides and achieve twice the result with half the effort. Carbendazim is a systemic fungicide commonly used by everyone. It can control dozens of fungal diseases. Ascomycetes and fungi imperfecti are especially sensitive to this medicine, but it is ineffective against bacteria and diseases caused by oomycetes among fungi. Therefore, when it is confirmed that a plant is infected with a fungal disease and repeated use of carbendazim is ineffective, consideration should be given to switching to phenylamide pesticides (such as metalaxyl). This type of medicine is mainly used for downy mildew, phytophthora disease, and pythium disease caused by oomycetes, while its effect on diseases caused by other fungi and bacteria is very poor. Chlorothalonil is a non-systemic broad-spectrum fungicide. It has a preventive effect on many plant fungal diseases. It can prevent pathogen spores from germinating, hinder mycelial development and spore formation, and can also control diseases that have developed resistance to carbendazim, but its control effect on diseases caused by soilborne pythium is poor. Therefore, often change fungicides (Huakang is said to be able to kill all diseases; I do not know whether this is true. When using it, I do not dare to be careless and still mix it with other fungicides) to strive for maximum protection of orchid plants, so that they are spared from the torment of disease. When orchids grow healthily, orchid friends are also happy.Figure 1 Ring spot disease + anthracnose "Colletotrichum"
Ring spot disease + anthracnose "Colletotrichum" usual preventive medication:
Pesticide name: 77% Kocide wettable powder; mode of action: broad-spectrum protective fungicide; method of use: 1000 times solution / 3-4 times / 7-day interval, spray / underside of leaves, upper side of leaves; can also prevent: brown spot disease, anthracnose, leaf spot disease, ring spot disease, bacterial brown spot disease;
Pesticide name: 25% Sportak emulsifiable concentrate; mode of action: broad-spectrum fungicide; method of use: 1500 times / 2-3 times / 8-day interval, spray / underside of leaves, upper side of leaves; can also prevent: anthracnose, leaf spot disease, sooty mold, black spot disease, round spot disease, ring spot disease;
Pesticide name: 80% mancozeb wettable powder; mode of action: broad-spectrum protective fungicide; method of use: 800 times / 3-4 times / 6-day interval, spray / underside of leaves, upper side of leaves; can also prevent: anthracnose, leaf spot disease, sooty mold, black spot disease, round spot disease, ring spot disease;
Ring spot disease + anthracnose "Colletotrichum" supplementary explanation:
1. Because most anthracnose control prescriptions are emulsifiable concentrates or mancozeb types, when using medicines, attention must be paid to weather temperature and UV index.
2. When the temperature exceeds 30 degrees, avoid using emulsifiable concentrates and copper agents as much as possible. When the UV index is too high, choose as much as possible to apply the medicine before 5 a.m. or after 6 p.m.
3. It is recommended that during normal medication, two prescription fungicides can be selected and mixed for use, so that multiple aspects of treatment and defense can be achieved.Figure 2 Ring spot disease + leaf spot disease
Ring spot disease + leaf spot disease usual preventive medication
Pesticide name: 80% mancozeb wettable powder; mode of action: broad-spectrum protective fungicide; method of use: 800 times / 3-4 times / 6-day interval, spray / underside of leaves, upper side of leaves; can also prevent: anthracnose, leaf spot disease, sooty mold, black spot disease, round spot disease, ring spot disease;
Pesticide name: 77% Kocide wettable powder; mode of action: broad-spectrum protective fungicide; method of use: 1000 times solution / 3-4 times / 7-day interval, spray / underside of leaves, upper side of leaves; can also prevent: brown spot disease, anthracnose, leaf spot disease, ring spot disease, bacterial
Ring spot disease + leaf spot disease supplementary explanation: Before the leaves of diseased orchids have dried and withered, if not carefully observed, ring spot disease is often mistaken for ordinary leaf spot disease or [text unclear]. Treatment [text unclear] is [text unclear], which is also a relatively easy disease to control.
2. It is recommended that during normal medication, two prescription fungicides can be selected and mixed for use, so that multiple aspects of treatment and defense can be achieved.Figure 3 Mild nutrient deficiency disease "zinc, magnesium, iron"
Mild nutrient deficiency disease "zinc, magnesium, iron" usual preventive medication: although this is a diseased state, it is not contagious. During normal fertilization, supplement some trace elements and fertilizers containing zinc, magnesium, iron, and calcium. Mild nutrient deficiency disease "zinc, magnesium, iron" supplementary explanation: during normal fertilization, supplement some trace elements and fertilizers containing zinc, magnesium, iron, and calcium.Figure 4 Soft rot + black spot disease
Pesticide name: 72% agricultural streptomycin sulfate wettable powder; mode of action: antibiotic fungicide; method of use: 800 times / 2-3 times / 7-day interval, spray, root drench; can also prevent: bacterial brown spot disease, soft rot disease;
Soft rot + black spot disease supplementary note: Because this is a condition caused by both fungi and bacteria occurring at the same time, two different fungicides must be mixed and used together. Since the two fungicides each have their own concentration dilution ratios when mixed, this often troubles beginner orchid growers. Here is a supplementary explanation: Ratio: you need 100 jin of water, use the bacterial-treatment streptomycin sulfate at 500 times dilution mixed with the fungal-treatment carbendazim at 1000 times dilution.
1. For 100 jin of water, streptomycin sulfate at 500 times dilution means 100 grams of streptomycin sulfate needs to be added.
2. For 100 jin of water, carbendazim at 1000 times dilution means 50 grams of carbendazim needs to be added.
3. That is, using 100 grams of streptomycin sulfate, which equals "500 times", plus 50 grams of carbendazim, which equals "1000 times", both added simultaneously into 100 jin of water and mixed for use - only then is the pesticide dosage correctly prepared.Image 5: Leaf tip anthracnose + leaf blight
Routine preventive spraying for leaf tip anthracnose + leaf blight
Pesticide name: 25% propiconazole emulsifiable concentrate; Mode of action: broad-spectrum systemic fungicide; Application method: 1500 times dilution / 2-3 times / 8-day interval, spray on leaf undersides and leaf surfaces; Also prevents: brown spot, round spot, anthracnose, leaf spot, leaf tip blight;
Pesticide name: 10% Score water-dispersible granules; Mode of action: broad-spectrum systemic fungicide; Application method: 3000 times dilution / 2-3 times / 8-day interval, spray on leaf undersides and leaf surfaces; Also prevents: brown spot, leaf spot, black spot, round spot, leaf blight, ring rot, leaf tip blight, sooty mold;
Leaf tip anthracnose + leaf blight supplementary note: Because this is a cross-symbiosis of two pathogens, it is recommended to use two fungicides for relatively simple control. The mixing method for the two fungicides is repeated here once more: when two disease conditions occur simultaneously, two different fungicides must be mixed and used together. Since the two fungicides each have their own concentration dilution ratios when mixed, this often troubles beginner orchid growers. Here is a new supplementary explanation: Ratio: you need 100 jin of water, use the bacterial-treatment streptomycin sulfate at 500 times dilution mixed with the fungal-treatment carbendazim at 1000 times dilution.
1. For 100 jin of water, streptomycin sulfate at 500 times dilution means 100 grams of streptomycin sulfate needs to be added.
2. For 100 jin of water, carbendazim at 1000 times dilution means 50 grams of carbendazim needs to be added.
3. That is, using 100 grams of streptomycin sulfate, which equals "500 times", + 50 grams of carbendazim, which equals "1000 times", both added simultaneously into 100 jin of water and mixed for use - only then is the pesticide dosage correctly prepared.Image 6: Leaf margin black spot disease
Routine preventive spraying for leaf margin black spot disease
Pesticide name: 80% mancozeb wettable powder; Mode of action: broad-spectrum protective fungicide; Application method: 800 times dilution / 3-4 times / 6-day interval, spray on leaf undersides and leaf surfaces; Also prevents: anthracnose, leaf spot, sooty mold, black spot, round spot, ring rot.
Pesticide name: 10% Score water-dispersible granules; Mode of action: broad-spectrum systemic fungicide; Application method: 3000 times dilution / 2-3 times / 8-day interval, spray on leaf undersides and leaf surfaces; Also prevents: brown spot, leaf spot, black spot, round spot, leaf blight, ring rot, leaf tip blight, sooty mold;
Pesticide name: 25% Sportak emulsifiable concentrate; Mode of action: broad-spectrum fungicide; Application method: 1500 times dilution / 2-3 times / 8-day interval, spray on leaf undersides and leaf surfaces; Also prevents: anthracnose, leaf spot, sooty mold, black spot, round spot, ring rot;
Pesticide name: 50% Sportak wettable powder; Mode of action: broad-spectrum fungicide; Application method: 2000 times dilution / 2-3 times / 8-day interval, spray on leaf undersides and leaf surfaces; Also prevents: anthracnose, leaf spot, sooty mold, black spot, round spot, ring rot;
Leaf margin black spot disease supplementary note: Actually, many of the fungicides used for orchid leaf diseases have similar properties, but as our professional introduction, we must present all the disease conditions for orchid growers to understand. In general, for fungicide selection, broad-spectrum and systemic pesticides are the two best types.
Experience reminder: In my experience, the key work when purchasing pesticides is to choose manufacturers with good reputation and clear ingredient labeling, lest you already have the psychological comfort of having applied a fungicide, only to find it was a fake product in terms of ingredients, causing the disease to go uncontrolled and missing the golden window for treatment.
Experience reminder: The second cause of harm is this: thinking that these pesticides may not have sufficient active ingredients, one instead increases the concentration and dilution ratio. Who would have known that this time you bought genuine pesticide - the result is that once you increase the ratio, it causes severe pesticide damage. Haha! You can only look to heaven speechlessly.Image 7: Damping-off disease
Routine preventive spraying for damping-off disease
Pesticide name: 72% Curzate wettable powder; Mode of action: systemic fungicide; Application method: 1500 times solution / 2-3 times / 10-day interval, drench root and stem; Also prevents: damping-off disease
Pesticide name: 50% Anchor wettable powder; Mode of action: systemic fungicide; Application method: 12500 times dilution / 2-3 times / 10-day interval, drench root and stem; Also prevents: damping-off disease
Supplementary note on treating damping-off disease:
1. During peak disease periods, continuous preventive spraying must be carried out. Having understood the characteristics of stem rot, we can only use targeted fungicides.
2. 72% agricultural streptomycin sulfate soluble powder at 800 times solution, 77% Kocide powder at 1000 times solution, spray on leaf undersides, leaf surfaces, and crown
3. Mepronil (emulsifiable concentrate) 1500 times + tetracycline (powder) 2000 times + dimethomorph (powder) 2000 times solution, spray on leaf undersides, leaf surfaces, and crown
4. Antracol 500 times + mepronil 1500 times + streptomycin sulfate 500 times solution, spray on leaf undersides, leaf surfaces, and crown. (When applying fertilizer or pesticide, you must spray the leaf undersides, because plants absorb through the stomata on leaf undersides.)
5. Every 20 days or so, use Dexon 800 times + tetracycline 3000 times solution to thoroughly drench the roots.
6. Fungicides must be alternated and rotated so as not to produce resistance and delay treatment of the disease.Basic principles of orchid cultivation and management techniques - Orchid cultivation techniques
1. Preparation of growing medium. Planting orchids requires a specially prepared growing medium, also called orchid mud. The growing medium for orchids should preferably be loose and breathable, well aerated, with moderate fertilizer content, and free of hidden pests and diseases. The composition of the growing medium is made from one or several basic components (substrates). These basic components include soil, fertilizer, and other materials, of which there are quite many types. Some components may seem unrelated to soil, but they are all substrates on which orchids depend for stabilizing the plant and for growth and development.
(1) Growing medium formula.
In East China, orchid growers generally prefer orchid mud from Shaoxing, Yuyao, and other places. In recent years, Emei He Wang Pai Xiantu has also become popular, but these growing media are limited in quantity and expensive, and can only be used for repotting. For large-scale ground planting, hundreds or thousands of tons of growing medium are needed, so only local materials can be used. After years of practice and repeated screening, we determined the best formula: four parts yellow sand soil, four parts sawdust, two parts river sand; if using yellow loam soil, then one part river sand, one part sawdust, one part yellow loam soil. All are thoroughly mixed. The pH value of the prepared growing medium should be between 6.5-6.8, loose and breathable, with excellent water retention and aeration, and comprehensive nutrition. River sand and sawdust serve to conduct water and air; sawdust is decomposed by bacteria and can slowly release nitrogen, phosphorus, potassium, etc. Yellow loam soil also contains various trace elements. After years of observation, this formula is very suitable for orchid growth. It is especially suitable as a substrate for domesticating and cultivating wild orchids. It is suitable for Cymbidium goeringii and Cymbidium faberi, and is also ideal for Cymbidium ensifolium and Cymbidium kanran. Whether in flowering rate or stress resistance, it shows significant improvement.
(2) Bamboo root soil.
This refers to the soil at the base of bamboo clumps that have been growing for many years. Due to the spreading of bamboo rhizomes and bamboo roots, as well as the decay of bamboo leaves and shoot sheaths, this soil becomes loose in structure, well-drained, and has a certain fertility without being excessively fertile, making it suitable for orchid growth. The quality of bamboo root soil depends on three factors: first, the original soil quality, which is the predecessor and foundation of the bamboo root soil, with sandy loam being the best; second, the age of the bamboo clump planting - the longer the time, the more fully the bamboo roots, bamboo leaves, and bamboo rhizomes have acted; third, the distance from the bamboo stump - the closer to the bamboo stump, the better the soil.
(3) Milk vetch chaff soil.
Milk vetch chaff is made by harvesting, sun-drying, and crushing the plants of green manure (Chinese milk vetch). Mixing milk vetch chaff with bamboo root soil or ordinary sandy loam, piling it up, and composting it produces milk vetch chaff soil. The preparation method is: choose a rain-sheltered site, spread a layer of soil, then a layer of milk vetch chaff, pour a round of *manure water, and pile up layer by layer in this way; after piling, sprinkle water on the surface to moisten it, then coat it with thin mud to seal it. After piling and fermenting for half a year, it can be used.
When using, mix it into other growing media in proportion.
(4) Leaf mold.
Made by piling up fallen leaves or green grass and tall stalks, watering or applying fertilizer, coating with thin mud to seal, and after composting and sieving. It is best to use green grass that has not set seed, and to compost it fully to kill pests, diseases, and weed seeds; otherwise, there will be many weeds in the orchid pots later.
(5) Mountain soil.
This is the forest soil where wild orchids originally grew. It is formed by dead branches and fallen leaves accumulating and decaying over many years, mixing with the soil. The naturally formed leaf mold contains rich humus, is loose and breathable, and is very suitable for orchid growth. When transportation is convenient, digging up mountain soil in large quantities for planting orchids is relatively simple and economical, and is even better for domesticating raw orchids. Humus soil under broadleaf forests, especially leaf mold under chestnut trees, is an ideal soil for orchids.
(6) Pond mud.
When repairing ponds and fish ponds in winter, dig out the mud, sun-dry it, then crush it into fine particles. It can be used to cultivate all flowers, including orchids.
(7) Field soil.
This means selecting loose topsoil from fields, mixing in a little sandy soil or a small amount of rice husk ash, then adding some composted manure or fermented organic fertilizers such as soybean cake and rapeseed cake, to improve soil structure and enhance fertilizer efficiency. After turning and mixing thoroughly several times, sieve it. This soil is nearly neutral and not as good as humus soil. Therefore, it is only used reluctantly when there is no suitable humus soil or mountain forest sandy loam, and is mostly used for cultivating common orchid varieties.
(8) Cow dung soil.
Crush and grind fermented dry cow dung into fine powder, mix it into sandy soil or field topsoil at a 1:3 ratio. It is best to select cow dung from cows fed dry feed in winter, because after dry forage is ruminated in the cow's stomach, although the fibers are fine and broken, they still retain elasticity and are plant fibers containing certain nutrients. This cow dung soil is soft and rich in fertilizer, extremely suitable for the air-loving nature of orchid roots. In Taiwan, China orchid circles, people often use this cow dung soil as a filling material for cultivating terrestrial orchids, with good results. Abroad, for cultivating terrestrial orchids, generally 5 parts humus soil or leaf mold plus 1 part sand is used; or 3 parts peat soil plus 1 part river sand, mixed with crushed dry cow dung, thoroughly mixed before use. For epiphytic orchids, the growing substrate is mainly moss and ferns, with a small amount of tree leaves, small pieces of charcoal, and crushed dry cow dung added. Before using soil to plant orchids, expose the soil to sunlight for disinfection and sterilization. In summer, spread out the soil and let it sun-expose for more than 3 days to kill pathogens and insect eggs. Before use, the growing medium should be tested and adjusted for pH value. For overly acidic soil, lime can be used to adjust it. For overly alkaline soil, superphosphate, ferrous sulfate, etc. can be mixed into the soil. In short, it is advisable to control soil pH at slightly acidic to neutral (i.e., pH 5.5-7). Using organic fertilizers, such as green grass and tree leaves composted into fertilizer, and adding them to the soil to change soil acidity and alkalinity is a better approach. In addition, before planting orchids, the nutrient soil should be sieved and graded, separating large particles from small particles.
When planting orchids, place the large particles at the bottom of the pot to facilitate drainage. At the same time, the degree of soil moisture should also be adjusted properly - neither too wet nor too dry. Ideally, squeeze the soil in your hand with force and it forms a ball; open your hand and shake it lightly, and the soil breaks apart into granules again. This degree of moisture is suitable.
2. Preparation of the orchid growing site. 1. Productive ground planting. The original environment for terrestrial orchids is growing in mountain forests and secluded valleys, with high, refreshing terrain, shade from trees, forming a moist microclimate. Small temperature differences, clean air.
When introducing and domesticating, one should first simulate their wild environment to achieve abundant flowers and lush leaves. At present, with industrial development and urban modernization, greening work cannot keep up correspondingly for the time being, and there is pollution from factories and vehicles. Therefore, orchids cultivated in cities are not as robust as those grown in suburbs. There is a gap with the original environment of wild orchids, and a great difference from the meteorological factors of the original habitats of Cymbidium kanran and Cymbidium ensifolium. Therefore, careful design was made for the domestication and cultivation site, and practical arrangements were made for adjusting environmental factors.
The orchid nursery covers about 15,000 sq m, rectangular in shape, with a rectangular pond for storing rainwater. In the nursery, every 2.5 m or so, a 2.5 m tall moso bamboo pole is fixed, with bamboo poles tied horizontally on top to form a frame, used to lay the first layer of shade netting. At 20 cm below the first shade net, another horizontal thin bamboo pole is placed to lay the second layer of movable shade netting. The first shade net is basically fixed from spring to autumn, while the second layer can be retracted or extended as needed. Carefully adjust light and temperature. The seedling bed width is 1.2 m, length 12-16 m (depending on terrain), height about 30-40 cm (5-7 bricks high), with 50 cm between seedling beds and 130 cm wide pathways. This facilitates daily management. In winter, a plastic greenhouse is erected over every two beds for warmth. On snowy days, pay attention to clearing snow to avoid excessive snow crushing the plastic greenhouse. About two water tanks with a storage capacity of 1 cubic meter are built per mu (one mu ≈ 667 sq m) to treat tap water. In winter, 100-150 watt light bulbs are set up about 4 m apart inside the plastic greenhouse, mainly for heating.
2. Open-field cultivation
(1) Ground planting of cymbidiums under tree shade.
This is for ornamental purposes, using sparse tree shade in front of houses, in wall corners, or in scenic areas for appropriate ground planting, but the original poor clay soil must be dug out and replaced with loose humus soil or good field topsoil.
When winter arrives, spread some rice straw over the soil surface at the roots to prevent frost damage to orchid roots. If there is severe cold, straw curtains or other soft coverings should also be laid over the leaf clusters to prevent cold damage. For this type of ground-planted orchid cultivation, apart from strengthened management and protection during the hottest midsummer, it can generally be managed extensively and allowed to grow naturally. Orchids planted in the open field are all common varieties without petal-type classification. In the following spring, after the weather turns warm, the cold-protection coverings can be removed. After years of growth, as long as water and fertilizer are applied in a timely manner, their adaptability is relatively strong, and they can bloom abundantly year after year, with delicate fragrance drifting far, making them a fine item for embellishing the countryside.
However, when arranging ground-planted orchid cultivation, in addition to considering the tranquility of the layout
(2) Pot cultivation of orchids.
This refers to growing orchids under a shade shed.
For pot cultivation of orchids, it is best to use clay pots, i.e., unglazed fired tile pots. They have good breathability, can filter water, and are inexpensive. They are economical and practical orchid-growing supplies. However, tile pots are rather rough and not attractive, and are not suitable for exhibition. Porcelain pots or glazed pots are attractive in appearance, but their breathability and drainage are very poor. If used for long-term orchid cultivation, they easily cause orchid roots to rot, making it difficult for orchids to grow vigorously. Therefore, when using porcelain or glazed pots for orchids, more drainage tiles or fillers such as clam shells must be placed at the bottom of the pot; moreover, watering must be controlled and not excessive. If growing orchids in clay tile pots, they can be placed inside larger porcelain or glazed pots during exhibitions. Yixing purple clay pots are attractive and elegant in appearance, and also have a certain breathability, making them relatively suitable for orchid cultivation. Newly purchased orchid pots must be soaked in water for several days; especially newly kiln-fired tile pots must be allowed to absorb enough water to completely eliminate their fiery dryness. For general orchid cultivation, newly planted orchids mostly use new pots, while repotting mostly uses old pots. For potted orchids, it is best not to place them directly on the ground, because they are easily disturbed by pests and weeds. Especially in hot summer, when the scorching sun is intense and ground temperature rises, it harms the orchids; during thunderstorms and plum rain seasons, the humid heat rises even more, easily steaming the orchid roots; furthermore, being close to the ground, ventilation is poor. It benefits aerial root growth. To reduce these effects, orchid pots can be placed on orchid benches made of cement boards, facilitating upward and downward convection, continuously supplying fresh air, promoting orchid respiration, enhancing metabolic function, accumulating nutrients and energy production, making orchids grow robustly, and also avoiding ants, slugs, and other pests harming orchid roots. If conditions are limited, an empty clay pot can be placed upside down on the ground, and the potted orchid placed on top.
3. Orchid room cultivation. The orchid room is mainly for overwintering terrestrial orchids.
Different types of orchids have different ecological habits, so the time for moving indoors for winter and the room temperature requirements also differ. For terrestrial orchids, as long as the temperature is not below 7°C-8°C, most can be cultivated in the open. In Jiangsu and Zhejiang areas, it is customary after the start of winter to move Cymbidium ensifolium, Cymbidium kanran, and Cymbidium sinense, which require slightly higher temperatures, indoors for cultivation, and to move some Cymbidium goeringii and Cymbidium faberi with flower buds to under the eaves or cold-protected places to avoid early frost damage affecting flower bud development. After minor snow, potted orchids grown from pseudobulbs and weak small plants, especially those with pure-color petals, are gradually moved indoors and placed on orchid benches near windows to receive sunlight. After major snow, all potted orchids are moved indoors for care. Before orchids enter the orchid room, first wash the area around the orchid pots clean, which both prevents mud from contaminating insect eggs and mold and also looks clean and elegant. When placing orchid pots, pay attention to reasonable arrangement, facilitating both sunlight penetration and ventilation. When terrestrial orchids overwinter indoors, the key is to manage temperature and humidity well. Generally, room temperature should be maintained above 7°C-8°C, and for Cymbidium sinense, ideally 10°C-15°C. After orchid pots are moved indoors, if the weather is not yet severely cold and freezing, open the south-facing windows around noon and open a small vent on the north side to facilitate indoor air circulation. In the evening, if the indoor temperature is still above 5°C, the small north and south vents can be slightly opened; if below 5°C, all windows should be closed. In deep winter, only around noon on windless sunny days, slightly open the windows for a little ventilation, and close the doors and windows once the sun shifts slightly, adding straw curtains or cotton curtains by evening. If the temperature continuously drops below 3°C-5°C, a coal stove with a chimney pipe can be used for heating. After the start of spring, as the climate gradually warms, all orchid room doors and windows can be opened around noon on clear days, but attention must be paid to temperature changes; in the afternoon when the temperature gradually drops, the south windows should be half-open and half-closed; before nightfall, close everything again.
During this period, the orchid room temperature should preferably be maintained at around 10°C. If the temperature is too high, it will cause early-flowering varieties of Cymbidium goeringii to bloom prematurely, and the flowers will also tend to wither early. At the beginning of spring, it is even more important to prevent late spring cold snaps from affecting flower bud growth or even freezing orchid roots.
After Awakening of Insects, all Cymbidium goeringii and Cymbidium faberi without flower buds can be moved out and placed on open-air benches, with reed curtains added over the shed frame at night to prevent frost damage. All types of orchids with flower buds should still remain in the orchid room for care, and can only be moved outdoors after Qingming; but at night, attention should still be paid to preventing late frost. During the indoor orchid cultivation period, especially in severe cold seasons, special attention must be paid to the dryness and moisture of potted orchids. Pot soil should preferably be dry. When watering is needed can be determined by looking at the pot surface: if the surface soil is in a powdery, loose state while the soil below is still slightly moist, do not wait until the pot soil is completely dry before watering. When watering, first move the potted orchid down and place it on the ground, and water along the water groove at the pot rim, taking care never to let water soak into the leaf clusters. The orchid pot can also be placed in a water vat for shallow soaking for a few minutes, with the water limited to reaching the middle of the pot. When watering, if water soaks into the leaf sheaths, it should be promptly wiped off with a dry cloth, or allowed to dry in the sun before moving back indoors. Because orchids are kept indoors for long periods, many dust particles often attach to the leaf surfaces, hindering metabolism. On clear, warm days, around noon, move the pots outdoors into sunlight and use a fine-nozzle watering can to spray and clean the leaf surfaces, washing away dust; after the water dries, move them back indoors. If the water has not dried, the wet parts of orchid leaves easily turn black and wither. When growing orchids indoors, during heating periods, indoor temperatures are often too high, the leaf clusters appear dry, the pot soil surface is dry and loose, or the moss on the pot surface looks withered. Then water should be sprayed promptly on pathways and walls to allow evaporation and regulate temperature. In short, for indoor orchid cultivation, whether the orchids in the pots or the moss on the pot surface, it is best to keep them green and lush. If you are an amateur orchid grower, due to limited conditions, you can use an outdoor south-facing sunny spot along a wall, using the wall on one side and bricks on the other three sides to build a single-slope ground box. The size can be determined by the number of pots. On the sloped surface of the ground box, install wooden-framed glass windows or plastic film windows that can be opened and closed. For orchids with long, tall leaves, place them in higher positions near the wall, on inverted empty flower pots, or on stacked bricks, wooden strips, or cement boards at suitable heights. Low pots are arranged row by row toward the front, and all leaf tips or the tops of encircling leaves must not touch the glass or plastic film of the windows. In severe cold seasons, whenever the temperature is too low or on snowy and windy days, the sloped windows must be covered with sufficient straw curtains or other coverings to prevent cold air from entering. In clear and mild weather, especially after the start of spring, when sunlight shines, the cold-protection straw curtains can be removed; when the midday sun is strong and the temperature is slightly higher, the covered windows can be lifted to leave a gap to regulate fresh air. After the sunlight shifts, the covered windows should be closed immediately. In daily care, great attention must be paid: excessive water droplets must not condense on the covering window glass, to prevent them from dripping into the leaf clusters; wet areas often turn black and rot, or even die.
3. Planting orchids. 1. Planting timing. Whether repotting or newly planting, the choice of timing has a great influence on the survival, growth vigor, and development of orchids. Therefore it is very important. Generally, the more suitable time is during the orchid's dormancy period, that is, March-April, before new shoots emerge; by solar term, it is between Spring Equinox and Qingming. If after new shoots have emerged, operation is very inconvenient, and a little carelessness can break or injure the new shoots. When the orchid's dormancy period is about to end, and new shoots and new roots are at the stage of being about to grow but not yet grown, planting at this time is optimal; shortly after planting, they can put out roots and shoots and resume normal growth. If planted too early, orchids do not easily recover after planting, and if encountering low temperatures, cold waves, late frost, or spring thunder, frost damage often results. In the Yangtze River basin, orchid rooms are seldom heated in winter. Winter is very cold, so division in severe winter is not advocated. To make division easier, the soil can be appropriately dried before division. This makes roots whiten and produce inconspicuous shrinkage, making the originally brittle and easily broken fleshy roots soft, so that during division and potting, not too many roots are broken. In larger orchid nurseries, the planting workload is heavy and takes a long time. Precious varieties should be arranged for planting at the optimal time. Common varieties can be delayed or advanced as appropriate.
2. Using orchid seedlings. For propagation, orchid seedlings that grow well and are free of pests and diseases should be selected.
After 2-3 years of cultivation, orchids need soil replacement or repotting, and at this time division propagation should be combined. When repotting, support the bottom of the flower pot with the left palm, carefully extend the fingers of the right hand into the orchid leaf cluster to block the pot soil, then lay the orchid pot on its side, tilting the pot body sideways toward the person, with the lower edge of the pot mouth touching the ground. At this time, lift the pot slightly upward with both hands, let the lower edge of the pot lightly tap the ground, loosen the pot soil, rotate the pot body, change the contact point of the lower edge of the pot mouth tapping the ground, and let the pot soil gradually loosen evenly and separate from the flower pot. Support the orchid plant with the right hand, and remove the flower pot with the left hand. If the orchid plant is too tall, it is advisable to tap the lower edge of the pot mouth against the edge of a wooden chair or cement platform, so that the orchid leaves hang in the air without being injured or broken. After the orchid pot soil separates from the pot, lay the orchid seedlings and pot soil flat so that the soil ball does not suddenly loosen and crack, causing orchid roots to break. Then carefully pat the soil ball gently to loosen it, and gradually shake off the old pot soil. Carefully grasp the pseudobulbs to avoid injuring leaves and tender shoots, especially protecting root tips. Cut off already yellowed and withered leaves, decayed bracts on pseudobulbs, and rotten, dry, hollow old roots. However, leaves on pseudobulbs with new shoots should be retained as much as possible to promote good growth of new shoots. For larger clumps that have been selected and cleaned, find the natural gap where two pseudobulbs are relatively far apart and easily loosened when shaken by hand, cut the two pseudobulbs apart - predecessors called this "opening the road" - then hold the bases of the two clumps with both hands and gently shake and slowly pull along the road to divide them into two clumps. Properly prune the separated orchid clumps, then soak them in a 800 times water-diluted thiophanate solution for 10-15 minutes. Only the roots should be soaked, not the leaves; a 1000 times water potassium permanganate solution can also be used for disinfection. Note: only disinfect the wounded parts, then air-dry the orchids in a cool, ventilated place. When the orchid roots become soft and easy to bend, they can be planted. Generally, in clear weather, air-drying for half a day is sufficient; of course, they must not be dried too much.
3. Planting procedure. For divided orchid clumps, do not split them too sparsely. Each clump should have at least 3-5 seedlings, and it is best to keep one-year-old plants, two-year-old plants, and three-year-old plants in the same clump.
(1) Pot padding.
Cover the drainage hole at the bottom of the pot with a piece of tile, then gradually fill with bricks, tiles, or shells, filling large gaps with mud particles or bean-sized stones, generally about 1/2-1/3 of the pot's internal height. The remaining clear height above is about 10-15 cm, reserved for the growing medium layer. The specific height should be determined according to the orchid type, the length of orchid roots, and the height of the pot. The padding material should not be packed too densely or too solidly; some gaps should be retained. Practice has proven that some new roots can grow well in the gaps of the padding layer.
(2) Planting.
On the padding layer, first fill 2-3 cm of growing medium, press lightly with the hand, then place the orchid upright on it. Depending on the plant and pot size, several single plants, 2 clumps, 3 clumps, or more clumps can be planted in one pot. 3 clumps are suitably planted in a tripod arrangement. 4 clumps can be planted in a square. 5 clumps are suitably arranged in a plum blossom shape. Orchid roots should spread naturally, and leaves should drape in all directions. Slowly place the orchid roots into the pot so that the roots spread naturally and touch the inner wall of the pot as little as possible. After the orchid plant is in the pot, gradually fix the orchid plant's posture. For one clump per pot, the old pseudobulbs should be placed to one side, leaving room for new shoots to develop. For multiple clumps per pot, the old pseudobulbs of each clump should be relatively gathered toward the center of the pot, so that new roots and new shoots developing outward each have enough space.
(3) Filling soil.
When planting, hold the leaves with one hand and add nutrient soil with the other, holding the base of the orchid plant and lifting slightly upward to spread the root system, while shaking the orchid pot. Let the growing medium penetrate deep into the root zone; continue adding soil and shaking the orchid pot to adjust the position and height of the orchid plant. Press along the pot edge with the hand, but never too heavily so as to injure roots. Continue adding soil and pressing until the pot surface soil is 2-3 cm above the pot rim, slightly mounded. The growing medium should cover all orchid roots, mounded up to the base of the pseudobulbs. As for the depth of soil filling, tradition holds that Cymbidium goeringii should be shallow and Cymbidium faberi deep, but generally the standard is not to bury the leaf bases on the pseudobulbs. When newly collected orchids grow in the wild, the plants retain obvious markers above and below the soil surface, which can be used as a guide. The size of the flower pot should also match the size and number of plants - neither a large pot with few small plants, nor a small pot with many large plants. Generally, the number of plants should be based on the principle that they will just fill the pot in 2-3 years. Plant size should match pot height. This is both beneficial to growth and meets ornamental requirements.
(4) Top dressing.
After planting is completed, spread a layer of small gravel or green moss on the surface of the pot soil. It is best to use high-quality moss from under the forest. It is not only attractive but also regulates moisture, protects leaf surfaces from muddy water contamination, prevents new shoots from being infected by pathogens in the soil and rotting at the core; in addition, it can reduce rainwater erosion of the pot soil and keep the pot soil loose.
(5) Watering.
After planting is completed, water for the first time immediately. The pot soil must be thoroughly wet. Water droplets should be fine and the force should not be strong. If placing in a water basin to soak, never soak too long. Once the pot soil is soaked, immediately take out the orchid pot, then move it to a shaded place for care.
4. Post-planting care and management. Mastering orchid planting techniques is certainly very important, but managing and caring for orchids well is even more difficult, hence the saying "three parts planting, seven parts care." Orchid care requires understanding the environment, accumulating care experience, and patience and attentiveness. The most important thing is to understand the laws of orchid growth and development - when they sprout, when they grow leaves, when they bloom, and when they go dormant. Then carry out care and management from aspects such as temperature, humidity, watering, fertilizing, ventilation, plant protection, cherishing leaves, and protecting flowers, and you will certainly grow orchids well.
1. Cherishing leaves. Orchid leaves are soft and beautiful but not weak, upright but not stiff.
Orchids are moving and lovely, but good flowers do not come often, and there is nothing to be done when flowers fall; but orchid leaves remain green through all four seasons, forever full of vitality, giving people year-round enjoyment. The elegance of orchids is displayed both in the flowers and entrusted to the leaves.
And lush leaves are the prerequisite for good flowers. When leaves are healthy and lush, the plant itself manufactures abundant nutrition, so flowers are many and beautiful. If leaves are damaged while flowers are many, it is merely a sign of rapid decline. The key to cherishing leaves is first to control shade density, air humidity, appropriate water and fertilizer, and maintain good ventilation. Make orchid leaves lush and healthy, verdant and glossy. Also strengthen pest and disease control, and prevent wind, rain attacks, and mechanical damage. In addition, preserve the leaf tips. The ends of orchid leaves are like sword tips, brush tips, and eyebrow tips, able to convey meaning and spirit. Losing leaf tips makes them appear abrupt and dull. The key to preserving leaf tips is ensuring the water and nutrients orchids need are sufficient, the pot soil is loose and breathable, so the root system is well developed and intact, the plant grows vigorously, and no scorched tips occur. Some people say that the sign of well-cultivated orchids is that the leaf tip can pass through the eye of a needle, which means the leaf tip is intact and the tip is undamaged. The leaf tip shapes of different orchid types differ: some are acuminate, some obtuse and rounded, some notched, some upturned; as for leaf color, some orchid varieties have gold or silver tips (that is, the leaf tip is yellow or white), showing their preciousness and rarity. This is another layer of interest in leaf appreciation regarding leaf tips. In daily care, pay attention to protecting orchid leaves, be light and careful in operation, do not bump orchid leaves, and maintain their natural posture.
Carefully clean contaminated leaves; sprayed water must not accumulate in the center of the leaf cluster. Withered yellow old leaves and diseased leaves should be cut off promptly. For partial cutting of orchid leaves, cut at an appropriate place with a slanted cut, and the resulting pointed angle should be less than 30 degrees. Some also cut twice, but it must not be cut flat.
2. Protecting flowers. After flower buds emerge, if there are too many, they consume excessive nutrients from the mother plant, hindering the formation and vigorous growth of leaf buds. Excess thin and small flower buds should be removed early. Keep one flower bud per orchid seedling.
Each pot should preferably retain 3-5 flower buds. Appropriately retain flower buds according to orchid variety, pot size, and number of seedlings. To protect and develop precious varieties, all flower buds can also be removed to allow lush multiplication. During the period from flower bud elongation to flowering, maintain moderate light so that flower color is fresh and full, rich in luster and full of fragrance. If light is too weak, flower color is pale and lacks luster, flowers bloom too long, consume nutrients, and hinder budding, leaf growth, and flowering the following year. Cymbidium goeringii flowers bloom for about half a month; after fading, the flower scape should be cut off promptly. For Cymbidium faberi flowers, when the last flower of the inflorescence has been open for 1 week, cut off the inflorescence. When breaking off flower scapes, steady the leaf base with one hand and push the flower scape to one side with the other, so it breaks from the base and can be pulled out, or it can be cut off. The removed flower stalks can be placed in a vase and enjoyed for many days. Generally, after flowering, orchids are not allowed to pollinate and set seed, especially not the less robust and precious varieties, otherwise it affects flowering the following year. If conducting cross-breeding, carry out artificial pollination at the appropriate time. And carefully manage the mother plant so that the seeds are full and mature.
3. Temperature. Most of China is in the temperate and subtropical zones, while orchids generally originate in places with mild, humid climates, relatively high average annual temperatures, and long frost-free periods. In Northeast and Northwest China, orchids are rarely cultivated, mainly due to temperature constraints. The northernmost distributed Cymbidium plants in China are Cymbidium goeringii and Cymbidium faberi. On their distribution line, there is frost or short-term snow accumulation in winter, and higher temperatures in summer. However, because orchids mostly grow in mixed broadleaf and coniferous forests or in bamboo forests, the trees both block the summer sun and resist the winter cold wind; even in places covered with snow, the impact on orchids is not great, because snow actually protects orchids through winter, and the ground temperature under snow is generally not lower than 0°C. In our introduction and domestication of Cymbidium ensifolium and Cymbidium kanran, we have moved them 600-1000 km north from their original habitats, and on a large-scale ground-planting basis. It can be seen that the survival ability and adaptability of orchids are still relatively strong. In most of Northeast, Northwest, and North China, winters are too cold, and outdoor orchid cultivation is unsuitable. From mid-to-late October to late April of the following year, for half a year, orchids need to be moved indoors or into greenhouses for cultivation. In the lower Yangtze region, orchids also need to be brought indoors in winter or heated in sheds. In Fujian, Guangdong, Guangxi, Yunnan, Sichuan, Taiwan, China, and other provinces and regions, Cymbidium kanran and Cymbidium ensifolium generally do not need indoor overwintering in winter. In Jiangxi, Hunan, and parts of Sichuan, certain measures are still needed in winter to protect orchids.
Temperature requirements of orchids: The temperature for orchid seed germination is: 21°C-25°C during the day, 15°C-18°C at night. The temperature required for grown terrestrial orchid plants is 20°C-22°C during the day and 13°C-0°C at night.
During the winter dormancy period of orchids, the temperature can be lowered. For example, Cymbidium goeringii and Cymbidium faberi require a minimum winter night temperature of 4°C-6°C, and dropping to 0°C is also acceptable; plant leaves can even tolerate -2°C to -3°C under dry conditions. Orchid flowers develop from flower buds, and flower bud differentiation is closely related to temperature and light. Predecessors did much research on orchid flower bud differentiation, concluding that a low temperature of 12°C-13°C is sufficient for flower bud differentiation, with not much relation to day length. But the more light orchids receive, the more pronounced the effect of low temperature on flower bud formation. Therefore, from late spring to autumn, placing orchids outdoors for cultivation produces better growth and development than indoors. The purpose of regulating temperature mainly has 3 aspects: preventing cold in winter, preventing heat in summer, and changing the flowering period. When winter temperatures are below 0°C, orchid leaves and flower buds are prone to cold damage, with water-soaked black spots appearing on leaves and flower buds wilting. If the temperature drops suddenly and sharply or there is severe frost, the damage is even greater. But winter temperatures being too high is also not good, because orchids are in a dormant state in winter, and too high a temperature interferes with dormancy. In summer, if the temperature is too high, orchids suffer from heat, leaves turn yellow, become rough and lusterless, and are susceptible to disease attacks, often with the leaf base beginning to rot. Orchid flowering period is very obviously affected by temperature. Under general conditions, appropriately raising the temperature can advance flowering. For example, the flowering period of orchids under plain and urban cultivation conditions is often 15-30 days earlier than under original wild conditions. Using this biological characteristic, temperature can be appropriately adjusted to advance the flowering period by half a month to one month. Especially for spring-flowering types, flower buds are generally already formed in July-September of the previous year. After they pass through the winter dormancy stage, appropriately raising the temperature can advance flowering to coincide with the Spring Festival holiday. But it must be pointed out that raising the temperature must be done gradually. Experiments show that rapid temperature increases instead produce inhibition and delay the flowering period.
Methods of regulating temperature:
Temperature greatly affects orchid growth and development. If too high, respiration accelerates and nutrient consumption increases; if too low, enzyme activity decreases, synthesis is low, and growth and development slow. What matters is that daily temperature differences and seasonal temperature differences must form, so that sprouting and flowering can occur. In temperature regulation for domestication and cultivation, we adopt the principle of approximating the original orchid-producing area. In summer, double-layer shade netting is used to shade the orchid nursery, with obvious cooling effects: when the air temperature reaches 35°C, the temperature in the orchid nursery is only 31°C-32°C. In winter, plastic greenhouses are used for warmth: when the air temperature drops to 0°C, the temperature inside the plastic greenhouse can still remain at 6°C-8°C, and the winter temperature difference is smaller than in the open field, which both benefits nutrient storage and prevents cold damage. In addition to building earthen orchid sheds and orchid rooms, temperature can also be regulated by planting trees, shrubs, vines, and lawns around the orchid nursery. In summer, they can absorb part of the solar radiation heat, and in winter they can slow the loss of heat from the ground and air. Taking lawn as an example, according to measurements, in winter the air temperature over grassland is higher than over bare ground, with a maximum daytime difference of up to 4.4°C, helping to avoid cold damage; while in summer the air temperature over grassland is much lower than over cement ground, helping to prevent heat and cool down. In summer, it is advisable to spray or sprinkle clear water in the air, on the ground surface, on flower benches, and on orchid leaves. Because water absorbs part of the heat when evaporating, it can play a role in cooling and preventing heat; similarly, expanding water surfaces nearby also has this effect, such as ponds, reservoirs, ditches, and water vats. For greenhouses, curtains need to be hung on the glass to block light and prevent heat. In hot weather, pay even more attention to ventilation and strengthening air convection for heat dissipation, partially lifting the coverings on the shed; in the orchid room, open doors and windows to avoid heat accumulation. In temperature regulation, in addition to air temperature, attention should also be paid to soil temperature. Orchid roots grow in the soil, and the temperature of the pot soil has a direct impact on their physiological functions. Under general conditions, soil temperature and air temperature are positively correlated: when air temperature is high, pot soil temperature also rises, but the change process is relatively slow. First, prevent direct scorching sunlight on flower pots, which heats the soil and pot and burns orchid roots close to the pot wall; also note that when watering, water temperature should be close to soil temperature and not too different. There is another issue worth exploring, namely the relationship between artificial protection and the orchid's own adaptability. Like all plants, orchids have adaptability to the external environment. They are not inherently delicate. Therefore, when orchid growers protect orchids from heat and cold, measures should be moderate. Covering too densely and for too long will inevitably weaken their resistance. In our orchid nursery, the Cymbidium kanran and Cymbidium ensifolium introduced and domesticated from 600-1000 km to the south are not only protected but also gradually allowed to strengthen their resistance and gradually adapt to the new environment.
4. Humidity. Humidity generally refers to relative humidity, commonly expressed as a percentage.
Orchids have no fibrous roots, much less root hairs, so their water-absorbing surface is small; on the contrary, orchid leaves grow in clusters. Leaf transpiration is relatively large, and only when the air is humid can the balance between water absorption and transpiration be maintained. In the original growing areas of orchids during the growing season, rainfall is abundant and the air is humid, with relative air humidity above 80%; especially Cymbidium sinense growing beside streams, often shrouded in water mist, with relative humidity around 90%. The reason orchid cultivation in the north is difficult is that dry air is one of the important reasons. Generally, growing orchids in urban homes and on balconies is not easy to succeed, and insufficient humidity is also a major factor. When air humidity is low, orchid leaves are rough, dull, and lusterless; when air humidity is suitable, leaf surfaces are moist and green. Usually, the humidity required during the orchid growing season should not be lower than 70%, and during winter dormancy about 50%; air humidity at night should be somewhat higher than during the day. Humidity and ventilation are two relatively contradictory factors: too much ventilation lowers humidity. In the winter and spring of the north, dry winds blow frequently and humidity cannot be maintained, which is unfavorable to orchid growth, so ventilation should be appropriately reduced.
Methods of regulating and increasing air humidity:
Plant a variety of trees, bamboo and grass around the orchid nursery. The root systems of these plants can absorb large amounts of water from underground and then release it through the leaves at the surface. They can also retain surface water and release it gradually through transpiration, increasing the number of water molecules in the air and thereby raising air humidity. When the ground is dry, sprinkle water on the ground, benches and walls, which also helps lower the temperature. You can also mist or sprinkle water in the space where the orchids are grown or on the leaf surface. However, misting or sprinkling the leaf surface should not be done in the evening; if you need to sprinkle the leaf surface in the early evening, make sure the leaves can dry again by night. In southern China there are sometimes long spells of overcast and rainy weather, especially during the plum rain season when humidity is excessive, so doors, windows and covers should be opened for ventilation. Orchids like warmth and moisture; when humidity is high and ventilation is good, orchids grow robustly. But when temperatures are low and there is no ventilation, water vapor condenses into droplets, which harms new shoots and easily triggers disease, so low temperature combined with high humidity should be avoided. In our large field beds for growing orchids, bricks are laid around the perimeter and moss is planted on top. Bricks and moss have a very strong capacity to absorb water and retain warmth; this economical and simple natural humidity-increasing measure is very effective.
5. Watering. When watering, attention should be paid to matters such as water quantity, water quality, water temperature, watering time and watering method.
In the classification of xerophytes, hygrophytes and mesophytes, orchids belong to the mesophytes and do not need excessive water, so the potting soil should not be too wet. This is determined by the structural characteristics of orchid rhizomes. The pseudobulbs of orchids are swollen and fleshy, with a cuticle on their surface, while the epidermal cells are thickened to form stone cells, and the stem is filled with vascular bundles. The pseudobulbs can store nutrients and water and do not lose them easily. Orchid roots are mostly fleshy, with the outermost layer being velamen tissue; the cells of the velamen tissue are elongated and polygonal. When the velamen tissue cells mature, the protoplasm disintegrates and thickened stripes form on the cell walls. The function of the velamen tissue is to protect the cortex, absorb water, and reduce and protect against the loss of water from inside the cortex. Therefore orchids should not be watered too frequently and the potting soil should not be too wet, so as to avoid root rot. In addition, judging from the places of origin of orchids, orchids mostly grow on hillsides, on both sides of ridges, and in rock crevices. These places have good drainage and no risk of accumulated moisture or standing water. It is precisely by adapting to such an environment that orchid rhizomes are structured to store and retain water and nutrients.
Principles of watering orchids:
The following conditions must be relied upon:
(1) The type of orchid.
Epiphytic orchids and those with aerial roots can be watered less; for example, Cymbidium hookerianum has aerial roots and can absorb water from the air, so it need not be watered too much. In addition, orchids with thick cuticles on their leaves should be watered less; for example, the leaves of Tiegusu have a thick cuticle and lose little water through evaporation, so watering must be strictly controlled.
(2) The growing season of the orchid.
In spring, as temperatures gradually rise, it is the season for new shoots to sprout, so watering should be timely. Water once a day or every other day to keep the potting soil moist. During this period, a lack of water will delay flowering and make the shoots weak. In summer, temperatures are high and evaporation is great; this is the period of leaf expansion and root emergence and of root and leaf elongation, so water once every morning, and in the evening if the potting soil is dry you can add some water to moisten the potting soil, thoroughly moisten the leaves, lower the temperature and reduce nutrient consumption, so as to favor growth and development. Entering autumn, temperatures gradually drop and orchids grow slowly; observe the dryness or moisture of the potting soil every day, watering when it is dry and leaving it alone when it is moist. In winter orchids enter dormancy. The potting soil should be slightly dry, and watering should be reduced or omitted, but attention must be paid to the potting soil to prevent it from losing so much water that it instead draws water out of the roots. At the turn of winter and spring, after Chunlan (Cymbidium goeringii) has formed flower buds, the flower buds begin to elongate, so the potting soil should also maintain a certain humidity. If the potting soil is too wet in winter, the water content of the orchid plant increases, which easily causes cold damage.
(3) The growth condition of the orchid.
Orchids with strong growth and good roots can be watered more; otherwise reduce watering as appropriate, and diseased plants should have their water even more strictly controlled. When orchids are sprouting and growing, water can be somewhat more; after sprouting it can be gradually reduced. When the new shoots gradually mature, water should again be somewhat less; when flower buds appear, slightly more water; and during flowering, water should not be too much, so as to prolong the flowering period. After the flowers fade, watering should be stopped for several days to let the potting soil dry slightly and the orchid rest a little, and then water again.
(4) The condition of the pot and the plant.
That is, water according to the material and size of the pot: water more for clay pots and large pots, and less for porcelain pots and glazed pots. Water more when there are many potted plants or when field-grown orchid plants are dense.
(5) The dryness or moisture of the potting soil.
The bases for watering, such as season, plant, weather, pot and soil quality, can all be comprehensively reflected by the degree of dryness or moisture of the potting soil, so the dryness or moisture of the potting soil is the direct and intuitive basis for watering.
It can be judged by observation and touch. If the potting soil becomes hard, its color becomes lighter, and the moss on the pot surface is dry and wilted, it indicates that the soil is dry, and water should be given at once. If the potting soil is dark in color, has a damp feeling, and the moss grows mold, it indicates that the soil is too wet and should not be watered. Generally, a soil moisture content of 15%-20% is suitable.
(6) Watering time.
Generally speaking, in spring and autumn it is best done in the morning; during the hot midsummer period it is best around sunrise and around sunset; in early winter and early spring it can be done when the sun is at its zenith and the temperature has warmed slightly. During the period when they are brought indoors to overwinter, watering must be done at noon on clear days. But care should be taken to avoid wetting the leaf surface or letting water seep into the leaf sheaths. Among the people there is some very valuable experience in watering orchids; for example, for Chunlan and Huilan (Cymbidium faberi) there is the experience of "not dry in autumn, not wet in winter" and "delighting in moisture in spring, liking slight dampness in summer and autumn, and needing moisture with dryness in winter." This shows that orchids have different requirements for water at each stage of growth and development, and management should be adapted to local conditions and handled flexibly. Generally after the Beginning of Spring, the climate gradually warms, the flower buds swell, and the soil should be kept moist, with misting once every 2-5 days. After Awakening of Insects, for flowerless Chunlan and Huilan grown in the open, where wind and sun easily dry the water in the pots, daily watering should be frequent, but the amount should not be too much; water once every 2-3 days or a small amount once a day. After the Beginning of Summer, for all orchids that have finished flowering (including Cymbidium kanran and Cymbidium sinense), the soil should be somewhat drier, because after flowering most have a brief dormant period, grow slowly, and lose less water from the leaves. From June, as the weather gradually heats up, the young shoots (that is, young buds) grow faster, and at this time more attention should be paid to soil moisture; frequently sprinkle clean water on the orchid leaves and benches to create a moist microclimate, which is favorable for the young shoots to elongate and put out leaves. During the plum rain season, watering should be controlled to reduce the occurrence of disease; leaf-variegated plants and some petal-type seedlings are even more prone to disease, so even more attention should be paid. During the three fu periods the climate is hot; in addition to strengthening shade, carefully maintain soil moisture and sprinkle clean water on the leaves and pot surface around sunrise every day. After White Dew it gradually turns cool in autumn, and there is also the nourishment of night dew; the new plants stop growing vigorously, and the orchid buds break through the soil and grow slowly, so watering can be reduced; but when the potting soil is found to be dry, it must be watered until moist. In late autumn, the new plants have gone from fresh green and tender green to deeper and darker shades. The flower bud sheaths are all visible, and prolonged rain and excessive moisture should be prevented to reduce rotting of the sheaths (that is, rotting of the bud sheaths); shelter should be provided from rain and more sunlight should be given.
(7) The water quality and water temperature for watering.
For watering orchids it is best to use collected rainwater, which is the cleanest and also neutral; river water is next; well water contains minerals and is mostly alkaline, so it is relatively poor; tap water contains disinfectants and is the least suitable for orchids. If tap water must be used, it should be stored in a water tank for more than 24 hours, and exposure to sunlight is even better; after the disinfectant in it has settled or decomposed, take the clear water on top to water the orchids. Besides this storage treatment, there is also an activation treatment, which is to keep fish, algae, chlorella, red floating algae and other aquatic organisms in the tank where tap water is stored, so as to improve water quality. But attention should be paid to whether the fish have diseases, to prevent contamination of the water quality. The temperature of the potting soil can directly affect the water-absorbing function of orchid roots. Therefore the temperature of the water used for irrigation should be very close to the potting soil temperature and the air temperature. In hot summer, after the pot and soil have been heated by direct sunlight, if cold water is suddenly poured on them, the temperature difference between the two is too great, which will disrupt the normal absorption function of the root system and affect physiological balance. Therefore, in summer orchids should be watered in the morning and evening, when the water temperature is close to the soil temperature. It is best to bury the storage tank or storage jar half in the soil, and add shade, so that in summer the water temperature will not become too high.
(8) Watering methods.
The commonly used methods of watering orchids are watering, misting and soaking. Usually a watering can, ladle or hose is used to water; when watering, pour slowly from the edge of the pot so that the water gradually seeps downward and toward the center; never pour it suddenly into the center of the leaf fan, and do not let the water splash up potting soil and dirty the leaves. Misting should soak through the whole pot, and you must not give only a half watering, that is, with water only in the surface layer while the lower layer gets none; if half waterings are given over a long period, the surface is wet while the interior is dry, so some orchid roots cannot absorb water for a long time and shrivel, while the upper orchid roots turn upward and grow, sprawling and coiling in the surface soil. Many people, for convenience and to save trouble, attach a rubber hose directly to the tap and irrigate the orchid pots, which is very harmful: first, the tap water has not been treated and the bleaching agent harms orchids; second, the water temperature differs greatly from the soil temperature; third, watering cannot be differentiated according to different situations. The misting method is to use a spray can to spray water on the leaf surface, which can both increase air humidity and soil moisture and wash away dirt on the leaves; this method is often used during the orchid growing season. Do not spray too much each time; the standard is that the leaf surface is wet but water does not run off. If too much water is poured into the leaf center and remains there for a long time, it will rot the new shoots. The nozzle holes of the spray can should be fine and dense, and the water droplets fine and even. The soaking method, also called seep watering, is to place the bottom of the orchid pot into shallow water and let the water gradually moisten the potting soil. The soaking time must not be too long; as soon as the surface soil is seen to be moist, take the orchid pot out at once. This method can keep the orchid leaf surface clean. In dry seasons, the orchid pot can also be placed in a shallow tray, and the pot absorbs the accumulated water in the tray and then moistens the potting soil, thus maintaining relatively stable soil moisture. The drawback is that the bottom hole of the pot is blocked by water, which affects air permeability to a certain extent.
6. Light and sunshine. Light refers to the quality and quantity of sunlight, including wavelength, spectral composition and light intensity. Sunshine refers to the duration of sunlight; generally, more than 14 hours of illumination is long-day, and less than 14 hours is short-day. Among plants, those that need long days to flower are called long-day plants; conversely, those that need short days to flower are called short-day plants. Light and sunshine are closely related to the growth and development of orchids.
Orchids' requirements for light:
There is a saying among flower growers: shade for camellias, sun for peonies, half shade and half sun for Cymbidium ensifolium. This shows that different flowers and trees have different needs for sunshine, and orchids need half-shade and half-sun light conditions. The effect of light on leaf color -- orchids have long grown in mountain forests and have developed a shade-tolerant habit, and do not like direct strong light. When light is too strong, the leaf color becomes pale green; if suddenly exposed to strong light, the leaf color quickly turns yellow, the leaf surface becomes rough, and the leaves may even scorch. With moderate light, the leaves are green with a fine texture and luster; with too weak light, the leaf color is dark green and loses its luster. The effect of light on sprouting -- the strength of light has a direct effect on the number of leaf buds and flower buds, the time they emerge from the soil, and their growth condition. With too weak light, orchids produce more leaf buds and fewer flower buds, and their growth is poor. Therefore, starting some time before flower bud formation, appropriately increasing light can promote flower bud differentiation and achieve the goal of more flowers. The effect of light on flower color and flowering -- the flower color of orchids is mainly determined by flower pigments, and the violet light and ultraviolet light in light are the main light energy that forms orchid pigments. Therefore, when light is strong the flower color is deeper and more vivid; when light is extremely weak the flower color is very pale, and compared with normal it may be mistaken for another variety. For example, in ancient times in Ningbo, Zhejiang, there was a type of Xuelan, produced on shady, north-facing slopes; if planted in a pot and given a little weak sunlight, it turned green, and so it was regarded as rare and precious, but today it is often encountered when collecting in the wild and can also be obtained by artificial cultivation. Some people use this to commit fraud and pass it off as a new variety, and those with insufficient experience are often deceived. If other conditions are the same, the orchid pot placed in a position with stronger light flowers first; this is because the accumulated illumination and accumulated temperature first reach a certain value. Some people have experimented and found that extending the light period to 14-16 hours can promote earlier flowering of medium-sized plants and small seedlings; but for mature orchid plants, a light period of no more than 8 hours can promote flowering. For orchids that flower in winter, short days and long nights and low temperature conditions must be met to promote flowering. For orchids that flower in summer, long days and short nights and high temperature are required to promote flowering. For orchids with flower buds, to make them flower earlier, appropriately extend light and increase temperature. In a small room, a 100-watt bulb can raise the room temperature by 3°C-5°C and can promote earlier flowering. The relationship between light and leaf variegation -- leaf variegation is the cultivation technique in which lines or spots appear on the leaves. Leaf variegation is related to light. Changes in light can be used to promote changes in leaf variegation. The method is to use robust growing orchid seedlings, with more than three plants connected together; before 9 o'clock in summer and before 10 o'clock in winter, expose the orchid pot to sunlight, insert a thermometer into the pot, and when it has been exposed to 30°C move it into the shade. When it drops to 25°C, move it out again into the sunlight. Repeat this over a long period. One shade and one sun, one cold and one hot, are favorable for the appearance of variable factors within the leaves; over the years, hard work pays off and variegated leaves may appear. But this must be premised on the existence of recessive variegation factors within the orchid leaves; the change in sunlight merely promotes their manifestation.
Bases and methods for regulating orchid light:
Liking half-shade and half-sun light is a common trait of most Cymbidium species, but there are also differences among the species. Spring-flowering types, such as Chunlan, Chunjian and Songchun, need relatively weaker light, and the shade level should be controlled between 70%-80%. Summer- and autumn-flowering types, such as Xiahui and Qiusu, need somewhat stronger light, and their shade level should be controlled between 60%-70%; Mojian (Cymbidium sinense) needs about 85%. The light duration and intensity of spring, summer, autumn and winter are all different and should be treated separately, adjusting the shade level well. Within a single day, morning and evening sunlight can be allowed, but the harsh midday sun must be blocked and regulated, and on cloudy days the shade level should be reduced. It is worth noting that after summer rainstorms, or when it first clears after long rain, orchid pots must absolutely not be exposed to the sun; the experience of predecessors: if exposed to the sun right after rain, the water in the pot is hot, which scalds the leaves and injures the roots. Although orchids are relatively shade-tolerant, they also have phototropism; in the same cultivation site, the flowers and leaves on the sunny side are always more luxuriant. Over time this makes the growth of flowers and leaves uneven, and they lean to one side. For symmetry and beauty, the direction of the orchid pot should be rotated and adjusted at intervals. If out of a special need for shaping or composition, to express a particular poetic or picturesque effect, the position of the light source can also be used to strengthen the tendency of flowers and leaves, achieving the beauty of dynamic balance and satisfying appreciation needs. To regulate shade level and light duration, there are usually the following methods: buildings -- build greenhouses, orchid pavilions, waterside pavilions and orchid corridors to place orchids, and use the light-transmitting and sun-shading properties of such buildings to regulate light. As long as the orchid pots are placed appropriately, the desired effect can be achieved; bamboo blinds or shade nets can be hung on the sunny sides of these buildings for regulation. For potted orchids kept on balconies, light is regulated by carrying them in and out; although this is hard and tiring, it also cultivates refined enjoyment, and there is pleasure in combining flower growing with fitness. Building frames -- shade frames can be built from bamboo, wood, angle steel and the like, covered with bamboo blinds, plastic film, shade nets and so on. Our method of regulating light intensity is to build bamboo frames in the orchid nursery and set on them double-layer shade nets with a 50%-70% shading rate; the upper layer is relatively fixed and is only rolled up in winter, while the lower layer can be put down or taken up. In midsummer use double layers, and in spring and autumn use a single layer; on clear summer and autumn days at noon use double layers, and on cloudy and rainy days use a single layer. In winter it depends on the situation: on clear days put down the lower layer, and on cloudy days roll up the lower layer, because in winter the light change inside the plastic greenhouse must not be too great; if it is too great, the temperature and humidity will also change accordingly, which is unfavorable for orchid dormancy. In addition, before the orchid flower buds are ready to open, there must be moderate scattered sunlight, otherwise the flower color is dull and not beautiful. Building trellises -- on the orchid cultivation site, build bamboo frames, wooden frames or reinforced concrete frames and let grape, honeysuckle, morning glory, Chinese trumpet creeper, cypress vine and other vines climb and spread over them, which both shades and is beautiful and practical. Deciduous vines shade in summer and let light through in winter, which is a natural regulation. Planting trees -- around the orchid nursery, plant evergreen trees, deciduous trees, bamboos and the like of different heights in combination to regulate light intensity.7. Fertilizing. Orchid roots have no fibrous roots, and within the roots there are symbiotic bacteria.
The root fungi absorb mineral nutrients from outside and supply them to the orchid, while the orchid root cells provide water and organic nutrients to the root fungi, forming a mutually beneficial symbiotic relationship in which they coexist. But a stable balance must be maintained between them for luxuriant growth. Preparing suitable nutrient soil and fertilizing appropriately to maintain the balance between the two can promote robust orchid growth. Previously some people thought that orchids grow in the mountains and are naturally refined, so plain water and clear wind alone could sustain them. Others love orchids too deeply and are too impatient, often applying strong fertilizer of high efficiency and high concentration, causing results contrary to their wishes. Therefore we must seriously explore scientific and rational fertilization.
(1) Types of fertilizer.
Fertilizers can be distinguished by their active ingredients, their properties and their methods of use. By active ingredients, they are mainly nitrogen fertilizers, phosphorus fertilizers and potassium fertilizers. Nitrogen is the main component of cell nuclei and proteins, and is also an indispensable element in forming chlorophyll. Nitrogen fertilizer can make orchid leaves lush and robust; otherwise the leaves droop and soften, sprouting is difficult, and the reproduction rate is low. Commonly used nitrogen fertilizers include compost, * manure and urine, urea, green manure, ammonium sulfate, ammonium nitrate and so on. Phosphorus is also a main component of cell nuclei and directly affects cell division, chlorophyll formation and protein synthesis and transformation within plant cells; it can promote flower bud differentiation and growth, and bring about large flowers, vivid color and strong fragrance. Commonly used phosphorus fertilizers include superphosphate, monopotassium phosphate, phosphate rock powder, bone meal, rice-washing water and so on. Potassium directly participates in photosynthesis, can make cell physiology normal, and is also related to the synthesis of carbohydrates, proteins and fats. Potassium fertilizer can make orchid stems, leaves and roots grow robustly, make leaves tough and not easily broken, and enhance cold resistance and disease resistance; it can also increase the fragrance of flowers. Commonly used potassium fertilizers include plant ash and potassium sulfate, and monopotassium phosphate is also a fertilizer containing relatively much potassium. Besides the three main elements nitrogen, phosphorus and potassium, orchids also need many trace elements such as calcium, magnesium, iron, boron and zinc; these can be satisfied in the prepared culture soil and generally need not be added separately. But the demand for nitrogen, phosphorus and potassium is relatively large and must be solved through fertilization, repotting and soil changing. By fertilizer properties, they can generally be divided into organic and inorganic fertilizers. Organic fertilizers include compost, green manure, barnyard manure and cake fertilizer. Before use, organic fertilizer must be fully fermented, and the fermentation time must be at least more than one month. Organic fertilizer can improve soil structure, increase soil humus, make the soil good in air permeability and water retention, and its fertilizer effect is also long, gradually decomposing to supply long-lasting nutrients for orchid absorption. Inorganic fertilizers, also called chemical fertilizers, have high nutrient content, are clean and odorless, do not need fermentation and can be diluted and used immediately; they are convenient and quick-acting, but their effect does not last long, and long-term use can deteriorate soil structure. Generally orchid growers oppose the use of chemical fertilizers. In fact, if orchids are mainly given organic fertilizer and chemical fertilizers are used in coordination, the effect is still very good. By method of use, fertilizers can be divided into base fertilizer and top dressing. Base fertilizer is fertilizer added to the soil when preparing culture soil or before planting, such as leaf mold, green grass compost, and sorghum husk soil; these are both the growing medium for orchids and base fertilizer. Silkworm droppings, * manure, cow dung, bone meal, hair, cake fertilizer and so on can all be used as base fertilizer, added to the bottom of the pot or turned under the soil as base fertilizer, but chicken manure and human feces should be avoided.
(2) Top dressing is fertilizer applied after orchids are planted, during their growing season.
Generally orchids are only repotted and the soil changed after 2-3 years of planting, and during that time nutrients must be supplemented, so top dressing should be applied.
Time of fertilizing:
During the spring and summer growing period of orchids, to make orchids grow robustly and vigorously, more nitrogen fertilizer can be applied. If it is a leaf-variegated variety, then apply less nitrogen fertilizer or none, because a dark green leaf color will affect the appreciation of the leaf variegation. When the summer temperature is above 30°C, do not fertilize, because the potting soil temperature is relatively high, water evaporates too quickly, and the concentration of residual fertilizer increases, which is harmful to growth. If fertilizer is applied too frequently in summer, it easily forces autumn shoots, and the plants that grow later are short and weak, and the next year's spring shoots will be inhibited as a result. When the temperature is below 10°C, do not fertilize, because at this time they are in a semi-dormant state and do not absorb nutrients. Fertilizer should only be applied when sunlight and temperature are suitable and photosynthesis is vigorous. In winter orchids are in a dormant state, so there is even less need to fertilize. From before the new orchid shoots' pseudobulbs grow to half maturity, around the time the leaf buds emerge from the soil and during their elongation period, this is the vegetative growth stage of the orchid, and slightly more nitrogen fertilizer should be applied, while phosphorus and potassium fertilizer should be less. After vegetative growth comes reproductive growth; the nutrients produced by photosynthesis are stored in the pseudobulbs and leaves for use in flowering or new shoot growth. At this time more phosphorus and potassium fertilizer is needed, and applying appropriate phosphorus and potassium fertilizer can promote full maturity of the pseudobulbs and the production of shoots and flowers. If orchid leaves are pale and yellowing and the plants are weak, it is mostly caused by lack of fertilizer, and top dressing should be applied in time. But sometimes leaves also turn yellow due to too strong sunlight. Diseased plants should not be fertilized; wait until the disease is cured and they have recovered before fertilizing. Robust orchid seedlings can be helped by more fertilizer.
Ancient orchid growers had this experience:
Never fertilize a thin orchid suddenly. Never keep a fat orchid thin for long. This means that a thin orchid that has never been fertilized cannot suddenly be given strong fertilizer, for it cannot absorb it and it is harmful. For orchids that are regularly fertilized, one also cannot go a long time without fertilizing. In short, uneven fatness and thinness is not beneficial to orchids. Usually Chunlan, Huilan and Jianlan begin to be fertilized in early May. In summer during the three fu periods and in winter from December to early February of the following year, no fertilizer is applied. From May, apply dilute fertilizer once every 2-3 weeks until the end of September. In early September apply dilute fertilizer once to Chunlan, and in late September fertilize Jianlan once. After each fertilization, clean water must be added the next morning, which facilitates absorption by the orchid and also prevents harm to orchid roots from improper concentration. Generally it is not suitable to fertilize before and after flowering.
(3) Fertilizing methods.
Fertilization must mainly use organic fertilizer, which can make the soil loose and well structured and is favorable for orchid growth. Also apply thin fertilizer frequently, that is, the experience of predecessors that it is best to apply frequently and dilute, and absolutely avoid sudden and thick applications, which is what people today mean by small amounts and many meals. When applying, dilute the water and fertilizer appropriately, then use a watering can to pour it around the roots, without contaminating the orchid leaves. If chemical fertilizer is used, the concentration must be even lower. During the orchid growing season, a water solution of 2‰ urea and 2‰ monopotassium phosphate can be used as top dressing 2-3 times.
8. Ventilation.
Ventilation is also very important in orchid cultivation and management, but it is often overlooked by people. 146 Zhuhongxinsu (Beijing). Good ventilation continuously supplies orchids with sufficient fresh air, which can promote photosynthesis, increase nutrient production, promote metabolism, and make orchids luxuriant. Ventilation in the orchid room and shade shed can regulate their temperature and humidity, making them favorable for orchid growth, and can also reduce the occurrence of pests and diseases. Orchid brown spot disease and southern blight mostly occur in poorly ventilated environments. The orchid-growing site must be open, the terrain should be slightly high, the flower benches should not be too low, and constant attention should be paid to ventilation. Orchids like soft breezes and gentle breezes but not sharp winds, and excessively cold or strong winds should be avoided. Orchid pots should be placed sparsely rather than densely, and sufficient distance should be kept between pots so that leaves are not damaged by rubbing against each other in the wind. If the site is small, the flower benches can be built in stepped form, which facilitates ventilation and also makes management and viewing easier. Each orchid pot should not contain too many or too densely packed plants. If the plants have multiplied and become too dense, they should be repotted and divided in time. Frequently clear away weeds, diseased leaves and fallen tree leaves and other debris in the orchid pots to facilitate ventilation within the pot. Daily work for field-grown orchids throughout the four seasons: in spring around Qingming, remove the plastic film from the greenhouse, then water thoroughly once; several days later apply once a 15-20 times diluted duck feather water or fertilizer water fermented from cake fertilizer. At the same time, spray once with 1‰ omethoate (containing 40% active ingredient) to kill insects. From May to July, apply once a month fertilizer water made from 5% duck feather water or cake fertilizer. In August apply once 3‰-5‰ compound fertilizer. After autumn begins, no more fertilizer is applied. Autumn management is extremely important, and we summarize it in two words: autumn tempering. That is, after autumn begins, orchids are no longer fertilized, water is controlled, and light is increased to prompt early maturity. Generally potted orchids must follow the golden rules of orchid growing: do not take them out in spring, do not sun them in summer, do not let them dry in autumn, and do not let them get wet in winter. But field-grown orchids are not entirely like this; in autumn they should be dry rather than wet. The reason is: although the air is dry in autumn, ground moisture still rises from the soil, so there is not severe water shortage; moreover, drought can temper the orchid's cold resistance and prepare it for overwintering. Autumn tempering can prompt nutrients to gather in the pseudobulbs, increase the protoplasm concentration of the pseudobulbs, lower the freezing point, and prevent cold damage. If orchid seedlings grow vigorously in autumn, then when a cold wave comes and the temperature drops sharply, they will inevitably suffer cold damage. Field-grown orchids cannot be moved indoors before severe winter arrives, so only through autumn tempering can they survive. November is a relatively busy season in the orchid nursery, and the main work is preparing for the orchids' overwintering. First, remove the upper shade net, then install the plastic greenhouse; the two ends of the greenhouse are not closed at first, and are only closed when the temperature drops noticeably, and on clear days open them at noon for ventilation. This month, spray once with 1:1 Bordeaux mixture. Entering the severe winter season, first, one must not water easily, and second, appropriately increase light. "Appropriately" means that in winter some clear days have relatively high temperatures, especially with the warming winter phenomenon in recent years; at such times the lower shade net should be put down so that the temperature inside the shed does not rise or fall suddenly. If the shade net is not put down and the temperature inside the shed reaches 18°C-22°C for several consecutive days, some new shoots will begin to sprout, and once a cold wave arrives and the temperature drops sharply, they will certainly be frostbitten. Therefore, in winter a dormant environment must be created for orchids, and dormancy must not be easily broken. In early spring, cold and warm air masses move frequently over the land, so management must be even more careful; otherwise orchid seedlings that have consumed nutrients through the winter are very prone to withering and yellowing. Light should be gradually and appropriately increased, and the plastic film must not be removed too early; only after the weather becomes steadily clear in early April can it be removed.
1. Potting soil requirements: it is best to use neutral to slightly acidic soil containing large amounts of humus, loose and well drained, with a pH generally around 5.5 to 6.5. In Sichuan, Emei Xiantu and "Xinghong brand" refined orchid growing medium are often used, and more commonly "bamboo root soil" and leaf mold from moist forests in mountainous areas are used to cultivate orchids.
2. Placement site: orchids can be grown outdoors and on balconies in spring, summer and autumn, and a site should be chosen that has good ventilation, moist air and no environmental pollution. Being near ponds and riversides is of course good, but at least there should be tall trees or bamboo groves and shade nets to reduce sunlight exposure and lower the temperature. Orchid pots are best placed on wooden frames (or steel frames); if placed on the ground, bricks should be used as a base. On home balconies, a small water tank made of galvanized iron sheet can also be used to store water with bricks placed on top for cultivation, increasing humidity.
3. Appropriate shading: most orchids belong to semi-shade plants, and most types fear direct sunlight and need appropriate shading. In early to mid-April, orchids can have the nets removed and windows opened, giving more sunlight to promote growth. In May, apart from the midday sun, they can get 6 hours of light; from June, provide shade all day; after October, apart from the midday sun, they can be kept fully open. Remember the saying: "More shade, better leaves; more sun, better flowers."
4. Rational fertilization: orchids are naturally "vegetarian," and fertilizing should depend on the chosen potting soil and growth condition. Those growing luxuriantly and without disease can be fertilized, while those growing poorly should not be fertilized or only lightly fertilized. Newly planted orchids whose roots have not fully developed in the pot must wait 1-2 years before fertilizing. Generally in June-July, when orchid leaf buds have elongated to about 1.5 cm, apply decomposed liquid fertilizer once every three weeks (the concentration should be dilute, about 10%). Avoid chemical fertilizers; in high-temperature seasons it is not suitable to fertilize. From August to September, apply diluted liquid fertilizer once every two to three weeks. Each time orchids are fertilized it should be done in the evening, and in the morning clean water should be poured, called "return water."
5. Appropriate watering: rainwater and spring water are best for watering orchids; tap water or rice-washing water must be left overnight before use. When watering, pour from the edge of the pot, and do not pour into the flower buds. The amount of water should be determined according to temperature, the dryness or moisture of the potting soil, and the growth condition of the orchid. Water more for large leaves and less for fine leaves. In April-May, when new shoots have not yet emerged from the soil, the potting soil should be somewhat dry, because if too wet the new shoots easily rot; June-September is the growth period of new orchid shoots, and the amount of water should be increased, watering once every morning on clear days or once a day, and absolutely avoid watering under the hot midday sun. In autumn, appropriately reduce the amount of water, and leaf-surface misting can be used to keep the potting soil moist; in winter the amount of water should be even more controlled, keeping it at "80% dry, 20% moist" as suitable.
6. Evening misting: orchids originally grow in an environment with moist air, so in dry seasons, besides shading, evening misting must also be done to increase air humidity and lower the temperature; water can also be poured on the ground (bench surface) where the potted orchids are, and "one cold and one hot" can even more stimulate orchid growth.
7. Wind and rain protection: "February ghost wind" causing old leaves to yellow and fall is a normal phenomenon, and withered branches and dead leaves can be cut away. Orchids can be exposed to light rain, but must avoid plum rain, rainstorms or continuous rain, otherwise the heart and leaves easily rot. In rainy seasons, a small amount of plant ash can be appropriately scattered.
8. Pruning and flower removal: during orchid cultivation, withered, yellowed and broken leaves and diseased leaves should often be cut away to facilitate ventilation. For precious orchids, if there are too many flower buds, keep only the strong buds, with 1-2 flower buds per pot as suitable. For Chunlan, remove the flowers half a month after flowering; for precious orchids, remove them after 7 days, so that the spring leaf buds grow robustly and bloom better the following year. For Jianlan, when the last flower on the inflorescence has been open for a week, cut it off 3 cm above the pot surface.
9. Cold protection and warmth: because orchid varieties differ and their places of origin vary, their cold resistance also differs, so the time to bring them indoors in winter and their indoor placement also differ. Cymbidium kanran, autumn orchids and Cymbidium sinense grow in the south and should be brought indoors (or have windows closed and nets drawn) when the temperature is 5°C, and placed as far as possible in a sunny spot facing south. Spring and summer orchids have strong cold resistance and can be brought indoors only when the temperature reaches 0°C, placed on the northeast side. Around noon on clear, windless days, windows facing south or southeast should be opened and nets drawn for ventilation. Autumn orchids must not have windows opened on clear days at 1-2°C. Of course, where there is a greenhouse, electric lighting can be used for heating.
10. Disease and pest control: potting soil should generally be sterilized (sun exposure can also be used) to prevent disease. Orchids are most prone to southern blight in rainy, high-temperature seasons; for a small amount, it can be brushed off with a damp cloth, and for many pots, 500-800 times Bordeaux mixture or thiophanate can be used, sprayed once every 7-10 days. Among pests, scale insects (commonly called "orchid lice") occur most; during the hatching period use 1% omethoate and 25% phosmet emulsifiable concentrate at 1000 times solution, spraying once a week. To treat the symptoms one must treat the root cause; pots should be placed with appropriate spacing and at different heights to increase air flow and ventilation and reduce the occurrence of disease.
However, different orchids have different cultivation methods.
Several aspects to note in orchid cultivation
Our country has a long history of orchid growing, and our predecessors have accumulated rich experience in orchid cultivation for us. We should thoroughly understand the experience of our predecessors, absorb its essence, and deeply recognize that: cultivation environment, growing medium, watering, fertilizing, and prevention and control of pests and diseases are the five major links in orchid cultivation and management.
1. The choice of environment is relatively important. Huilan mainly grows under shrubs in subtropical mountain forests, and has developed the growth habit of liking half shade and half sun and liking moisture and air flow. As long as the growth rules of orchids are grasped and environmental conditions close to those of orchids are provided or created, all parts of the country are suitable for cultivating Chunlan and Huilan.
2. Use of growing medium. According to cultivation experience in various places, as long as it is slightly acidic, no matter what growing medium is used (including soilless culture), orchids can be grown well; the issue is that different growing media should be managed by different methods. Flower pots are best made of clay pots or Yixing clay pots, because orchids are aerial-root plants and air permeability of the pot is very beneficial to orchid growth.
3. Rational watering is the key to growing orchids well. The water used for watering orchids must be clean and slightly acidic, and must never be sewage carrying pathogens. The watering method should differ according to the plant. Loose mountain soil holds sufficient water; granular soil plus stone and volcanic rock also absorbs water relatively fully but does not accumulate water. After different growing media have been given one thorough watering, when the pot surface is seen to be dry and the growing medium about one centimeter deep has turned white, then to raise air temperature you can spray the pot surface, increasing the moisture of the upper growing medium so that the orchid plant and pseudobulbs maintain a certain moisture, and when the whole pot from top to bottom has not yet dried through, water heavily again, a thorough watering.
4. Fertilizing: on the basis of mastering watering well, in order to promote better growth and development of the orchid plant, fertilizing becomes even more important. Organic fertilizer, that is farmyard manure, should be dilute and can be applied once every ten or more days; other inorganic fertilizers (chemical fertilizers) should be used according to the instructions. During the orchid growing season, foliar fertilizer can be applied as a top dressing outside the roots. Base fertilizer is also very important; when repotting and changing soil, an appropriate amount of base fertilizer can be added without the fertilizer touching the orchid roots. Too much fertilizer easily burns orchid roots and causes black spots; if fertilizing is done properly it can produce strong seedlings and good flowers. The general requirement for fertilizing orchids is small amount, clear, dilute and light, truly achieving thin fertilizer applied frequently.
5. Pest and disease control: insect pests are easy to prevent and fungal diseases are hard to cure. If scale insects and other pests are found on orchid plants, omethoate or decamethrin can be sprayed according to the instructions for treatment, preferably mixed and used, 2-4 times a year. General fungal diseases such as black spot can also be treated; fungicides such as copper hydroxide, thiophanate-methyl and chlorothalonil can be used according to the instructions, with regular alternating treatment and preventive spraying every 15-20 days during the growing season. If virus-like soft rot (rot coccus disease) is found, it is an incurable disease among orchids and cannot be cured at all; once found, remove it promptly. Therefore when buying orchid plants, great care must be taken not to buy lower-priced diseased plants and bring them home, thereby affecting other precious orchid plants.
Different orchid types have different temperature requirements. For Chinese orchids, the most suitable temperature for vegetative growth is 20-30°C, the adaptive temperature range is 5-35°C, and the temperature for the reproductive period is generally between 5-15°C. Night is 3-5°C lower than day. When the summer temperature is above 30°C, the higher the temperature, the more orchid growth is inhibited. But under ventilated conditions, Chinese orchids are not harmed by short periods of high temperature up to 35-42°C. When the temperature is below 12°C, growth is slow. When the temperature is below 12°C, Chinese orchids shift to reproductive growth. Cymbidium sinense originally grows in subtropical mountain forests; in summer, daytime temperatures can reach about 32°C, while at night it is relatively cool, with temperatures generally not exceeding 20°C, and winter temperatures do not fall below 10°C. Cymbidium kanran and Jianlan originally grow in transitional subtropical mountain forests. Chunlan and Huilan mostly grow in temperate mountain forests; in temperate regions, summer temperatures reach as high as about 38°C, but in shaded mountain forests daytime temperatures do not exceed 30°C, and at night are around 18°C. In winter, under short-term snow cover, the surface temperature still exceeds 5°C and has no effect on flowering. Indoors they can also overwinter at around 0°C. The suitable growth temperature for Chunjian is 18-28°C, not exceeding 35°C in summer and not below minus 2°C in winter, and the reproductive growth temperature is 8-18°C. The temperature requirements for Lianbilan are generally not below minus 12°C in winter; in the reproductive period in spring and autumn, the temperature should not be below 12°C; in the summer growing period, temperatures mostly between 15°C-32°C are suitable, with 35°C as the critical line for growth, beyond which growth stops again.
The driving force of orchid life -- light
"All things grow by the sun." This sentence highly summarizes the enormous role of light in the growth, development and continuation of generations of living things, especially plants. The orchid plant itself relies on the photosynthesis of green leaves to obtain energy to maintain and continue life and carry on the generations; sunlight is the driving force of orchid life. But for orchids, which require a half-shade and half-sun habit, overly strong light is also harmful to orchid growth, and light suitable for orchids must be regulated and controlled according to the temperature, humidity and growth habits formed under the ecological environment of various orchid plants in different seasons, so as to satisfy and benefit the survival and growth of orchids. Below I will talk about some immature views on the close relationship between light and orchid plants, to explore somewhat with fellow orchid growers, which may be of some use for growing orchids well:
Below we explore from five aspects:
One, the relationship between light and orchid plant growth.
Two, the effects of light on orchid leaves, buds and flowers:
Three, the role of light in fertilizing and sterilizing orchid plants.
Four, the light intensity for orchids.
Five, artificial regulation of light.
One, the relationship between light and orchid plant growth.
Suitable light can promote normal orchid growth: orchid growth relies on the photosynthesis of green leaves to obtain energy to maintain and continue life, and light's effect on photosynthesis in Cymbidium plants is accomplished through light quantity and light quality.
① "Light quantity." That is, light intensity. Plant photosynthesis changes with changes in light intensity, and photosynthetic intensity is in direct proportion to light intensity. That is, when light intensity doubles or halves, photosynthetic intensity also doubles or halves. Through the chemical action of chlorophyll in orchid leaves, light enables the absorption of carbon dioxide and release of oxygen to increase the nutrients the orchid body needs. The bulbs and roots carry out digestion and decomposition at night, converting carbon dioxide into sugar, then forming various needed proteins, and by the flow and pressure of water and air these are transported to all parts of the plant, so potted orchids can grow shoots and flower. Photosynthesis has a heat limit and a cold limit, that is, the highest temperature and the lowest temperature, also called the critical points of photosynthesis. Too much and too strong sunlight, exceeding the critical point, can cause leaves to become dwarfed and yellowed, or even age prematurely and stop growing grass, gradually declining and dying; conversely, if light is insufficient, although the plant still grows, the nutrients produced are not enough, which is likewise unfavorable for healthy orchid growth. Therefore the level of a plant's light compensation point and light saturation point directly affects the accumulation of organic matter and healthy growth of orchid plants. To make crops grow well, attention should be paid to lowering the light compensation point and raising the light saturation point. The usual measures are: for sun plants, rational close planting and control of population development to ensure the plants have enough light, and if natural light is insufficient, increase artificial light; for shade plants, pay attention to moderate shading while satisfying their light intensity for photosynthesis as much as possible. Letting orchids have relatively abundant light of sufficient duration is beneficial.
② "Light quality." The regulation of light should consider not only light quantity but also light quality. The intensity of plant photosynthesis varies with light quality. Sunlight contains seven kinds of visible light as well as invisible light such as ultraviolet. Orchid leaves respond only to red, orange, yellow and blue-violet series of light. The different colors of sunlight cause differences in the intensity of plant photosynthesis; red light and blue-violet light are more efficient, while yellow-green light is lower. Not only does the intensity of photosynthesis differ, but the photosynthetic products are not entirely the same either; for example, plants growing under blue-violet light have increased amounts of protein and fat in their photosynthetic products, while under red light more carbohydrates are formed. Infrared light irradiation is favorable for plant cell division, showing as thickening in plants; far-infrared light irradiation is favorable for plant cell elongation, showing as growing taller in plants; ultraviolet light irradiation is favorable for orchid internodes becoming shorter, showing as dwarfing in plants. Therefore, supplemental lighting for orchids should set different light qualities according to the specific conditions and requirements of orchid seedling growth (ordinary incandescent lamps have less blue-violet light and more infrared light than the sun; fluorescent lamps have more blue-violet and green light and less red light; the visible part of xenon lamps is close to sunlight, but their ultraviolet and infrared light are greater than the sun's). Orchid cultivation generally uses mostly red light and blue-violet light. Experts suggest that supplemental lighting for Chinese orchid cultivation should use more red light. Of course, if conditions permit, choosing plant lamps designed specifically for orchid supplemental lighting is even better.
In short, according to the type of photosynthetic products required as mentioned above, one should consider comprehensively, make up for deficiencies by drawing on strengths, and choose suitable light sources to promote normal orchid growth.
Two, the effects of light on orchid leaves, buds and flowers:
1. The effect of light on orchid leaves.
① Orchid leaves under different light conditions: Orchids have long grown in mountain forests, developing a habit of partial shade and partial sun. They prefer diffused light and dislike direct, intense light. When light is too strong, orchid leaves tend to be shorter, thicker and stiffer, with a rough surface, and the leaf color turns pale green. If suddenly exposed to strong light, the leaves quickly turn yellow, the surface becomes rough, and the leaves may even scorch. With moderate light, the leaves are green with a fine texture and luster, and the plant grows robustly. When light is too weak, the leaves are emerald green, thin and long without luster. In short, the stronger the light, the yellower the leaf color; the weaker the light, the deeper the green. Either too strong or too weak light will affect the perfect growth of orchids.
② Changes in light can promote the expression of leaf variegation. Plants with the potential for variegation can receive a longer photoperiod; for line-variegated orchids, sunlight from 6 AM to 9 AM is best. Someone conducted an experiment: before 9 AM in summer and before 10 AM in winter, place the orchid pot in sunlight with a thermometer inserted in the pot, and when it reaches 30°C, move it into shade. When the temperature drops to 25°C, move it back out into sunlight. Repeat this over a long period. Alternating shade and sun, cold and heat, is beneficial for the appearance of variable factors within the leaves; over many years, variegated flowers and leaves may appear. However, this requires the prerequisite that recessive variegation factors already exist within the orchid leaves; the change in sunlight merely promotes their expression and has no inevitable connection. The white-spot-forming cells are the decisive factor and play the determining role in orchid line-variegation changes.
2. The effect of light on sprouting. Light can increase the sprouting rate of orchids. Orchid sprouting cannot rely solely on water and fertilizer management; appropriately increasing light is crucial. The sprouting rate is generally higher under strong sunlight. Strengthening light can not only increase the sprouting rate but also make new shoots stronger.
① Shallow planting of orchids produces more sprouts. Orchid growers generally believe that "deep planting is not as good as shallow planting" because when orchids are planted deep, the pseudobulbs are buried deep and receive less light. Under the same fertilizer and water management conditions, deeply buried pseudobulbs are smaller and produce fewer sprouts in spring. With shallow planting (half the pseudobulb exposed above the soil), the pseudobulbs are larger and produce more sprouts in spring. This is closely related to the light spectrum and the length of light exposure. It also demonstrates the principle that light can increase the sprouting rate of orchids.
② Light can promote flower bud differentiation and achieve the goal of more blooms. This is because light is the source of nutrients for flower bud differentiation and growth. The intensity of light has a direct impact on the number of leaf buds and flower buds, their emergence period, and their growth conditions. Orchids with sufficient light produce more nutrients through photosynthesis, have more flower bud differentiation, more blooms, deeper flower colors, and larger and better flower shapes. Conversely, orchids with too weak light may grow luxuriantly, but the nutrients produced are insufficient, resulting in more leaf buds and fewer flower buds. Even if they bloom, the flower color is paler, the flower shape is poorer, and the growth vigor is poor. Therefore, appropriately increasing light starting some time before flower bud formation can promote flower bud differentiation and achieve the goal of more blooms.
3. The effect of light on flowering:
① Light intensity and flower color changes. Sunlight is the fundamental source of color for all things in the world. The seven colors of the rainbow can change in countless ways, and the original colors of orchids are composed of ever-changing primal light. Violet light and ultraviolet light in the spectrum are the main light energies that form orchid pigments. Therefore, sunlight has a direct influence on the colored flowers of orchids. Strong light makes flower colors deeper and more vivid; excessively weak light makes flower colors extremely pale. For example, to make the flower colors of red-flowered varieties beautiful, sunlight can be slightly increased; to make blue-flowered varieties produce beautiful flowers, sunlight should be reduced. Colored flowers should be appropriately shaded during the flowering season, because under sunlight red and green light are not absorbed, while form-type flowers should be given more sun to thicken the petals. When cultivating colored flowers, paying attention to and controlling light during cultivation can make the flower colors more beautiful. Green and white flowers need reduced light; red, yellow, pink, and purple flowers need increased light. For example, if Cymbidium goeringii blooms in shade, the flower quality and color are better than when it blooms in sun (except for colored flowers), and the flower stalk is also longer. For Cymbidium faberi and Cymbidium ensifolium, stronger light is beneficial for flowering, producing larger flowers with good color and fragrance. Therefore, controlling and regulating reasonable light is a cultivation technique that must be mastered to fully display the best flower color.
② The effect of light on orchid blooming.
For orchids with flower buds, early or delayed flowering can be achieved by regulating the length of the photoperiod. Appropriately extending light and increasing temperature, such as using a 100-watt bulb or infrared lamp in a small room to raise the room temperature by 3°C—5°C, can promote earlier flowering. Similarly, orchids with flower buds placed in a location with weak light and low temperature can also delay flowering. For orchids that have already formed flower buds, appropriately extending sunlight and raising the temperature, or using a 100-watt bulb or infrared lamp in a small room to raise the room temperature by 3°C—5°C, can accelerate the flowering period and promote earlier blooming. Conversely, reducing light in a low-temperature environment can delay the flowering period. Because raising or lowering temperature can accelerate or slow down the physiological activities within the plant, using this biological characteristic, some have experimented with extending the photoperiod to 14—16 hours, which can promote early flowering of medium-sized plants and small seedlings; but for mature orchid plants, a photoperiod of no more than 8 hours can promote flowering. Appropriately adjusting light intensity can make orchids bloom at the right time, especially for species that bloom in spring, which generally form flower buds by July—September of the previous year. After they pass through the winter dormancy stage, appropriately increasing light and raising temperature can advance flowering to coincide with the Spring Festival holiday. Conversely, appropriately reducing light and lowering temperature can also delay flowering to coincide with orchid exhibitions. In short, regulating light intensity can make orchids bloom at the right time.
III. The role of light in fertilizing and sterilizing orchids.
1. The relationship between light and fertilization. Generally, how to shade and supplement light for various orchids in different seasons and at various growth stages so that orchids receive suitable light intensity is of concern to everyone. However, in the process of orchid cultivation, the question of how to correctly handle the relationship between fertilization and light may not necessarily be taken seriously, yet it is equally important for the vegetative growth of orchids. The strength or weakness of light leads to the strength or weakness of assimilation. If light is too weak, the assimilation of leaves is also insufficient, leading to poor digestion of nitrogen fertilizer during the day, less accumulation of sugars and starch, and therefore less decrease at night. Over time, leaves become very long while roots remain very short. If light is too strong, the assimilation of leaves becomes excessive. Orchid respiration increases, consuming excessive nitrogen fertilizer, causing leaves to become short, small, and yellowed. At the same time, abundant sugars and amino acids cause excessive growth of pseudobulbs and roots. These two adverse growth conditions may have multiple causes, and light is not the only factor (such as long-term dryness of the potting medium, excessive nitrogen fertilizer, high-carbon growth, small day-night temperature difference, nitrogen deficiency, etc., can also cause these problems). Failure to correctly handle the relationship between fertilization and light is also one of the important reasons, and must be given attention. The cultivation measures for such situations are: when orchids show a "long leaves and short roots" condition, light intensity must be gradually strengthened, organic nitrogen continuously supplied, and water supply reduced. After new roots grow out, they will slowly return to normal. When orchids show a "small leaves and strong roots" condition, light should be reduced, and sufficient inorganic nitrogen continuously supplied. This can both reduce sugar content and promote protein synthesis, and the new growth will return to normal.
Practice has proven that orchids can only absorb nutrients under conditions of sufficient light. Therefore, when fertilizing orchids, there must be moderate sunlight. The best time to fertilize is on a morning with good weather. When applying chemical fertilizers, the light intensity should be relatively higher; when applying organic fertilizers, it should be relatively lower.
2. Sunlight is a good weapon for sterilizing orchids and preventing disease. Light can not only raise temperature, but ultraviolet light in the spectrum can kill and prevent the growth of fungi, pathogens, and viruses. Pathogenic bacteria generally find it difficult to survive under blazing sunlight. Therefore, exposure to sunlight can sterilize and disinfect pots and potting media. However, for sterilizing and disinfecting orchids, the use of sunlight must be timed. For example, in winter, sun the orchids so that the entire plant bathes in ample sunlight; in summer, avoid the blazing sun at noon and in the afternoon. Light can also close the stomata of orchid leaves, blocking pathogenic fungi that easily invade through stomata. We have found that orchid plants with good light exposure have strong disease resistance, while orchid plants with poor light have stomata that are often open and are susceptible to infection by pathogens. Orchid plants with insufficient light are prone to pests and diseases. Using sunlight for sterilization and disinfection has always been advocated by orchid growers. The photosynthesis of orchids, like other biochemical processes, cannot exist in isolation and is also constrained and influenced by external environmental conditions. These external factors are: light intensity, carbon dioxide and oxygen concentrations, wind speed, temperature, water supply, inorganic nutrients, and pollutants in the atmosphere and soil, etc. In addition, photosynthesis is also affected by the plant's own internal factors, such as chlorophyll content, degree of stomatal opening, and the physiological state and structure of the leaves themselves. By improving these internal and external factors, the goal of increasing the plant's photosynthetic efficiency can be achieved, promoting healthy development, growth, and flowering of orchids. In summary, according to the growth habits of orchids, providing appropriate light can improve fertilization efficiency, enhance disease resistance, and benefit the healthy growth of orchids. For this reason, orchids that are weak, do not bloom, and are prone to pests and diseases must be given stronger light.
IV. Light intensity for orchids.
1. Orchids grow in mountain forest areas, and their ecological environment has fostered a need for partial shade and partial sun light conditions. There is a folk flower saying: "Shade for camellias, sun for peonies, partial shade and partial sun for four-season orchids." This shows that orchids have a partial shade and partial sun light habit, and the growth of all types of orchids cannot be separated from light. This is also a "common characteristic" of orchid plants.
2. The light requirements of various orchids are not entirely the same. Due to differences in ecological environments, various orchids have different light requirements, ranging from strong to weak. Generally speaking, Cymbidium faberi and Cymbidium ensifolium need more light for growth and can be shaded less. However, in the vigorous growing summer and early autumn, strong direct light will still scorch some leaves, causing them to turn brown, and even causing leaves to scorch and wither. At this time, shading is necessary, blocking 70%--80% of sunlight. Cymbidium kanran and Cymbidium sinense require relatively less light, and in summer should be shaded from 80%-85% of sunlight. For newly potted plants, diseased and weak seedlings, old plants, particularly delicate plants, and plants that have not been hardened off and have long been in partial shade and partial sun, shading must be provided during the growing period. For edge-variegated, striped, and crystal orchids, especially transparent types, they cannot tolerate relatively strong direct light. Shading must be provided when sunlight is strong. The amount of shading is also a rough estimate, because different varieties under the same species do not have absolutely identical light requirements. For example, variegated orchids, colored flowers, and strong versus weak plants of the same species all have different light requirements. This is the "individuality" of orchid plants, and growers need to observe carefully to correctly master the appropriate light for each type of orchid.
3. Orchids can be roughly divided into three categories: sun-loving, semi-shade, and shade types. They can also be divided into long-day and short-day types. Long-day orchids bloom as days gradually lengthen and nights gradually shorten, such as Cymbidium ensifolium and summer Cymbidium kanran that bloom in late spring and summer. Short-day orchids are the opposite, blooming as days gradually shorten and nights gradually lengthen, such as Cymbidium goeringii, Cymbidium goeringii var. longibracteatum, Cymbidium faberi, and Cymbidium sinense that bloom in late autumn and winter.
4. Reference values for optimal sunlight intensity for various orchids (unit: LUX)
Orchid species Sunlight range Optimal light intensity Light intensity for variegated orchids
Four-season orchid 10000-14000 **** 10000
Cymbidium faberi 9000-13000 11000 9000
Cymbidium goeringii 8000-**** 10000 8000
Cymbidium goeringii var. longibracteatum 8000-**** 10000 8000
Cymbidium lianpan 8000-**** 10000 8000
Cymbidium kanran 8000-**** 10000 8000
Cymbidium sinense 4000-****5000 4000
"Fairburn and Pringle pointed out: No one can propose the best light quality and light quantity for orchid growth and development, because these are complex factors involving light, temperature, different times, carbon dioxide concentration, day length, nutritional conditions, humidity, and the temperature difference between day and night, etc." ---- Excerpted from Wu Yingxiang's "Chinese Orchids." Therefore, the sunlight intensities above are only reference values.
5. The light intensity for orchids changes with the seasons: In winter and spring, orchids should receive more sunlight and basically do not need shading. In summer and autumn, sunlight before 8-9 AM should be fully utilized, but afternoon west-facing sunlight must be avoided, otherwise orchids are prone to disease. Sunlight and temperature have a great influence on orchid reproduction. If there is no sunlight for a long period in winter and the temperature is relatively low, it will affect the development of winter buds, leading to fewer and poorer-quality seedlings in spring and affecting the annual propagation rate.
6. Orchids prefer light in a cool environment. Generally, shading begins when spring passes and summer arrives, and ends only after late autumn. In summer, shade 40-50%; in late autumn, winter, and spring, full light exposure is suitable. Generally speaking: at 20-25°C, under direct sunlight, the chemical reaction between chlorophyll in orchid leaves and light is rapid, and the plants grow vigorously. Above 30°C, chlorophyll in the leaves automatically decreases, the leaf color becomes lighter, and a gray visible film gradually forms to reflect sunlight and prevent scorching. This condition can only be maintained for a short time; if it lasts too long, starting from the leaf tips, the entire plant gradually withers and dies, especially older plants which first turn yellow and then scorch. Therefore, the length of light exposure for orchids changes inversely with temperature.
7. Orchids prefer morning sunlight. When the morning sun first rises, the sunlight angle is low, and orchids receive light over a large area. Also, because morning sunlight is blocked by morning mist, the light is relatively soft, and direct exposure will not scorch orchid leaves. After nighttime nutrient accumulation, orchids have the strongest photosynthetic capacity in the morning.
V. Artificial regulation of light.
Light that is too strong or too weak is harmful to orchid growth. Orchid light requirements vary greatly with season, weather, region, and environment. If light is too strong for these reasons, artificial shading must be used to adjust the shade density and reduce light for orchids. If light is insufficient for these reasons and affects the healthy growth of orchids, artificial lighting must be used to appropriately supplement light so that orchids have relatively abundant light of sufficient duration. In short, to give orchids appropriate light, artificial regulation is necessary.
1. Basis for regulating orchid light:
① Regulate the appropriate light for various orchids based on differences in their light requirements. Different orchid varieties have different photosynthetic capacities and optimal temperatures. For example, different orchid species and variegation types will differ at different times and in different regions. On scorching days in midsummer and golden autumn, regarding shading requirements: the shade density for Cymbidium ensifolium is 60%-70%, Cymbidium goeringii and Cymbidium faberi require 70%-80% shade in summer, while Cymbidium sinense needs about 80-85%. Ordinary line-variegated orchids can have about 80%, while high-grade line-variegated orchids, crystal-variegated orchids, and pattern-variegated orchids should have about 90%. Flower-type orchids and ordinary line-variegated orchids can receive full light before 9 AM and after 4 PM on sunny days; high-grade line-variegated orchids, crystal-variegated orchids, and pattern-variegated orchids should receive semi-shade. In high-temperature "furnace" regions, the shade density should be increased by more than 5% accordingly. In winter and spring, appropriately increasing the light amount by 20% is more beneficial for orchid growth.
② Adjust the shade density according to the photoperiod and light intensity of different seasons. From late spring to summer and autumn, shade 40%--50%; in winter and early spring, 10%---20% light. Insufficient light will make orchid leaves soft with deep color, and cause leaves near the rhizome to bend downward or outward. Especially during the leaf emergence period, it causes leaves to grow rapidly. Conversely, excessive light will cause leaves to turn yellow or chlorophyll to be destroyed, leading to cell death, and excessive light makes leaves shorter and thicker and causes them to open prematurely or bend outward. Therefore, except in early winter and midsummer, move orchids outdoors in the morning until 9---10 AM so they receive sufficient light. As the angle at which sunlight strikes the earth shifts, the photoperiod and light intensity will change. In the winter and spring seasons with short and weak light, except that high-grade line-variegated orchids, crystal-variegated orchids, and pattern-variegated orchids need 60%-70% shading, all other orchids can receive full light, or semi-shade from 10-14 o'clock on sunny days. In the summer and autumn seasons with long and strong light, the shading time and density for orchids must also be adjusted accordingly.
③ Based on weather changes. With ever-changing weather such as sunny, partly cloudy, cloudy, overcast, and rainy or snowy days, light also changes frequently. Therefore, the shade level must be appropriately adjusted according to weather changes and light intensity. In particular, high-grade line-variegated orchids, crystal-variegated orchids, and pattern-variegated orchids cannot tolerate strong light, and if the shade level is not adjusted in time, it often leads to sunburn damage. In addition, if a fixed shade density is maintained regardless of light intensity, the sprouting rate and flowering rate of orchid plants will naturally not be as good as with timely adjustment.
④ Based on daily sunlight changes. When it turns from sunny to overcast, from overcast to sunny, from sunny to rainy, or clears up after rain, morning and evening sunlight can be allowed to shine freely, but the harsh midday sun must be blocked and regulated, and on overcast days the shade density should be reduced. It is worth noting that after summer rainstorms, or when it first clears after prolonged rain, orchid pots must absolutely not be exposed to the sun. Previous experience says: "If exposed to sun immediately after rain, the water in the pot heats up, scalding leaves and damaging roots."
⑤ Based on differences in climate and light intensity in different regions for specific regulation. China is vast, and climate and light intensity vary greatly, but the standards for strong, weak, and appropriate light for orchid growth are still unified, and specific regulation can be carried out according to local climate.
⑥ Based on temperature regulation. Orchid photosynthesis is closely related to temperature. Generally speaking, Chinese orchids carry out normal photosynthesis at 5-36°C, with the optimal temperature being 18-28°C. At temperatures as low as 0°C or as high as 40°C, which are the limits, orchid photosynthesis is inhibited. Starting from the low-temperature limit, photosynthesis strengthens as temperature rises. Beyond the optimal point, photosynthesis declines; above 36°C photosynthesis is very weak, and at the 40°C limit photosynthesis stops. When temperature is high, use shading to cool down; when temperature is low, use heating equipment to raise the temperature, thereby achieving a more suitable temperature, promoting orchid photosynthesis, and ensuring healthy and rapid growth of orchids.
⑦ Based on the phototropism of orchids. Orchids have phototropism, so the direction of the orchid pot should be rotated and adjusted at intervals to prevent the plant and leaves from leaning to one side. In particular, the side with new growth should face the direction of ample light during the sprouting period to facilitate sprouting and healthy growth of the shoots. If for special needs of shaping or composition, to express a specific poetic or artistic conception, the position of the light source can also be used to strengthen the directional tendency of flowers and leaves, achieving the beauty of dynamic balance and satisfying appreciation needs.
⑧ Based on the growth condition of orchids. Generally speaking, if the leaf color is pale green and the orchid leaves are weak and spindly, then light is too strong. If they appear yellow-white or even scorched and withered, it indicates that light has exceeded the orchid plant's tolerance. Conversely, if the color is dark green or deep green without luster, it indicates that light is too weak. Regulate shading well based on the growth condition of orchids. In addition, if stems and leaves are relatively dense and soft, with many leaf buds and few flower buds, then light is insufficient; conversely, if stems and leaves are sparse and firm, with few leaf buds and many flower buds, then light is too strong. Both are abnormal and need timely adjustment.
⑨ Regulate light based on the growth stage of orchids. During the growing period, the light supplementation time should be longer; during the dormant period, it should be shorter.
⑩ Based on professional testing. (Excerpt)
(1) The light intensity for well-growing orchids is 4000--5000 Lux (lux, the unit of light intensity), at which the sprouting rate, flowering rate, leaves, and leaf color are all excellent.
(2) From professional testing practice, it has been found that orchids have a saturation point for light requirements. After light reaches the saturation point, even better sunlight is harmful rather than beneficial to orchids.
(3) Plants most easily absorb red and blue light, and a balanced combination of red and blue light is especially important for photosynthesis. Experiments have proven that red light can promote orchid growth, while blue light is indispensable for thickening leaves, accelerating plant development, and regulating stomatal opening. Green light also cannot be ignored, as it can promote oxygen production, thereby helping orchids better accumulate nutrients.
(4) A certain intensity of long-wave ultraviolet light is also essential, as it helps form anthocyanins and inhibit the elongation of branches and leaves.
2. Methods for regulating orchid light:
First, shading. In nature, orchids mostly grow in cool, shaded mountain forest environments with diffused sunlight. Semi-shade and shade types account for more than four-fifths of all orchid family plants. Therefore, when light is too strong, shading must be used to reduce light.
(i) Plant shading. Imitating the natural environment, using plants for shade is one of the more ideal methods. The method is: at the orchid cultivation site, set up bamboo frames, wooden frames, or reinforced concrete frames, and let grapevines, honeysuckle, morning glory, Chinese trumpet creeper, cypress vine, and other climbing plants spread over them. This provides both shade and beauty. Deciduous climbing plants provide shade in summer and let light through in winter, which is a natural regulation. Trees can also be planted around the orchid garden, using a combination of evergreen trees, deciduous trees, and bamboo of different heights to regulate light intensity.
(ii) Shade net shading. The shade structure can be built with bamboo, wood, angle steel, etc., covered with bamboo blinds, plastic film, shade nets, etc. A double layer of 50%-70% shade-rate shade net should be installed on top; the upper layer is relatively fixed and only rolled up in winter, while the lower layer can be deployed or retracted. Use double layers in midsummer, single layer in spring and autumn; use double layers at noon on sunny days in summer and autumn, and single layer on cloudy and rainy days. In winter, it depends on the situation: deploy the lower layer on sunny days, roll it up on cloudy days. In addition, before orchid flower buds are about to open, there must be moderate diffused sunlight, otherwise the flower color will be dim and not show its beauty. It is best to install shade nets in an adjustable manner so that the shade density can be increased or decreased as needed. The shade net should as much as possible not be placed tightly against the plastic film or glass on the roof of the structure, and there should be a gap of about 30 cm between net layers. The shade net should be placed outside the plastic film or glass for the best shading effect. If placed inside the structure, the shading effect is greatly reduced. When growing orchids on a balcony, during midday when sunlight is direct and light intensity is strong, and when walls have reflected light and radiant heat, ventilation is also poorer than in a courtyard or orchid nursery. Therefore, in high-temperature seasons, a 50% shade net should be hung outside the security grille for 3-4 hours around midday to prevent scorching orchid plants. When sunlight is slanting and the temperature has dropped, it should be rolled up promptly to allow ventilation. Orchid shading requires a certain regularity. Generally speaking: large-leaved species need more than small-leaved species; low-altitude species need more than high-altitude species. More shade is needed in summer, less in winter; more shade at noon, less in the morning and evening; more shade at high temperatures, less when cool, etc.
Second, "light supplementation." Regulating light in orchid growing locations is not just about shading; when natural light is insufficient, artificial lighting must be added to appropriately supplement light for orchids. This is especially true for indoor orchid growing and after the onset of winter when the photoperiod is short, which has a certain impact on orchid growth. Only by supplementing light to meet the light requirements of orchids can orchid plants develop properly, have sturdy stems, and grow and bloom.
(i) Basis for light supplementation. How to supplement light appropriately and what kind of light to supplement? There must be a scientific basis. Sunlight is a collection of continuous spectral bands from red to violet, and artificial simulation of the plant growth environment should also start from this. In addition to considering the light quality and light intensity necessary for orchid growth, artificial light supplementation also needs to consider the physiological radiation characteristics of the light source. (Light waves that match the characteristic curve of plant chlorophyll synthesis are called physiological radiation light sources, i.e., photosynthetic light waves.) Under different light qualities, not only does the intensity of photosynthesis differ, but the photosynthetic products are also not entirely the same. For example, plants absorb red light most strongly, followed by blue light. When plants grow under blue-violet light, the amount of protein and fat in their photosynthetic products increases, which is effective for thickening stems and leaves, accelerating plant development, and regulating stomatal opening. Under red light, more carbohydrates are formed, which can promote orchid growth. Violet light and ultraviolet light mainly form anthocyanins and inhibit the elongation of branches and leaves (ultraviolet light must not be too strong, as it will scorch orchid leaves). Green light also cannot be ignored, as it can promote oxygen production, thereby helping orchids better accumulate nutrients. In addition, a certain intensity of long-wave ultraviolet light is also essential, as it helps form anthocyanins and inhibit the elongation of branches and leaves. Light supplementation must be based on the effects of the above spectra and the growth condition of orchids when selecting appropriate light sources.
(ii) Light source selection. Since light quality has a clear impact on the composition of photosynthetic products, people should select appropriate light sources based on the type of photosynthetic products needed. Ordinary incandescent lamps have less blue-violet light and more infrared light than the sun; fluorescent lamps have more blue-violet and green light and less red light. Generally speaking, orchid cultivation can use a mixed light of red, blue, and white tubes to supplement insufficient light. A complete combination of red and blue spectra can enable orchids to achieve optimal growth. Philips' tri-phosphor 6400K fluorescent lamp can basically meet the growth requirements of orchids and is inexpensive. Of course, if conditions permit, it is best to choose plant lights specifically designed for orchid light supplementation. They are a bit more expensive but have better results. Using LED lighting, the plant growth rate and photosynthetic rate both increase by more than 20%. LED lights have particularly strong durability compared to ordinary lights and save electricity, reducing operating costs. When choosing a light source, one should consider not only light quality and light quantity, but also low power consumption, economy, durability, and ease of use.
(iii) Light supplementation time. After installing artificial lighting equipment in the orchid room, the light supplementation time should be determined based on the actual light conditions of the orchid growing location, seasonal light changes, weather changes, and the growth stage of the orchids. The light supplementation time varies according to different orchid growth stages and growing environments. For indoor orchid growing where light is not strong but diffused sunlight can enter, there should be no less than 5 hours of light supplementation; for balconies, no less than 4 hours of artificial light supplementation; for basements and indoor spaces without sunlight, no less than 10 hours of artificial light supplementation. During the orchid growing period, the light supplementation time should be longer; during the dormant period, it should be shorter. On cloudy, rainy, and foggy days, there should be no less than about 10 hours of artificial light supplementation. Light supplementation time involves many factors and requires experimentation in practice to determine the more correct light supplementation time.
(iv) Light distance. Light intensity is inversely proportional to the distance from the light source to the leaf surface, meaning the closer the distance, the stronger the light intensity. Therefore, the height and distance of the light tubes can be adjusted to regulate light intensity, to meet the appropriate light requirements of different orchid species. How to choose the light distance: the installation distance of supplemental lights should be set according to the power of the lamp and the height of the orchids. The closer the distance between the lamp and the orchids, the higher the light utilization, but care should be taken to avoid the distance being too close, which would cause excessive temperature and harm the orchids. Fluorescent lamps and plant-specific light sources (40W) should be at a distance of 20-40 cm; incandescent lamps (100W) should be installed at a certain height from the plants, because incandescent lamps radiate a large amount of infrared light that converts to heat, so 70 cm or more is better; high-pressure sodium lamps (120W-400W) should maintain a vertical distance of 1 m-1.5 m from the plants. For LED supplemental light sources, since LEDs produce very little heat, they can be placed at a close distance, about 10 cm.
(v) Light direction. To ensure the light supplementation intensity for orchids, the lights should as much as possible be arranged directly above the orchids. Benefits: First, due to plant phototropism, with more overhead light, the orchid leaves will have stronger upright growth, meeting the aesthetic requirements of orchid lovers. Second, if the angle of light matches the growth angle of plant stems and leaves, the light intensity received per unit area is higher, which helps improve light energy utilization efficiency.
(vi) Precautions for light supplementation.
① It is best not to supplement light at night, because orchid growth requires a certain period of darkness to regulate the respiratory function within the orchid plant and to carry out the transformation and synthesis of dry matter within the plant.
② Pay attention to ventilation. Most supplemental lights generate heat, especially in summer, which can raise the temperature of the orchid room or orchid shed and cause orchid diseases. Ventilation can reduce heat.
③ Comprehensive configuration of light sources. To obtain better light supplementation results, light fixtures of different light sources need to be comprehensively configured, such as a combined configuration of fluorescent lamps and incandescent lamps, or a combination of low-pressure sodium lamps and incandescent lamps, to meet the orchid's needs for various spectra.
④ Pay attention to the safety of supplemental lighting fixture installation to prevent accidents.
The above briefly describes the role of artificial light supplementation for orchids and some specific issues. In summary, through appropriate light supplementation for orchids, ensuring that orchids have relatively sufficient light can not only improve the cold resistance of orchids during winter but also ensure the vigorous growth and abundant flowering of orchids in the coming year.
Third, "hardening off." Orchids have relatively strong adaptability to light, which is also related to the number of generations exposed to light intensity. They will gradually change and adapt. For orchids that have always been grown in shade, if the plant's light conditions are artificially changed, after a period of time, the structure and function of their chloroplasts will undergo a certain degree of change to adapt to the new light conditions. For example, under weaker light conditions, plant leaf structure and function will develop in a shade-tolerant direction, enabling them to maintain relatively high photosynthetic efficiency under weaker light; conversely, under stronger light conditions, plants can also adapt to a certain extent, effectively utilizing ample sunlight for photosynthesis. The folk term "hardening off" roughly means this -- letting orchids adapt to different environments -- including light, temperature, etc. Through "hardening off," plants can be strengthened generation by generation.
Fourth, display. In the display of potted orchids, according to the habits of various orchids, those with high light requirements should be displayed in locations that receive the most light. Those with low light requirements should be displayed in locations with less light. In addition, orchids have phototropism, so it is best to adjust the pot direction once or twice a month to prevent the plant and leaves from leaning to one side. In particular, the side with new growth should face the direction of ample light during the sprouting period to facilitate sprouting and healthy growth of the shoots.
In summary, light plays a vital role in the growth, development, flowering, and reproduction of orchid plants. Although orchids prefer shade, if all things in the world had no sunlight, they could not carry out photosynthesis to produce nutrients. They could not survive. Therefore, light is the driving force of orchid life. Photosynthesis is also a quite complex issue. Orchid photosynthesis, like other biochemical processes, cannot exist in isolation and is also constrained and influenced by external environmental conditions. These external factors are: light intensity, carbon dioxide and oxygen concentrations, wind speed, temperature, water supply, inorganic nutrients, and pollutants in the atmosphere and soil, etc. At the same time, light is also affected by the plant's own internal factors: for example, different orchid family plants have certain differences in light duration, intensity, and requirements. Also affected by chlorophyll content, degree of stomatal opening, and the physiological state and structure of the leaves themselves. Only by improving these internal and external factors can the goal of increasing the plant's photosynthetic efficiency be achieved, promoting healthy development, growth, and flowering of orchids.