How to care for potted orchids in October? A full breakdown of the key cultivation points

In October, with clear autumn skies and crisp air, temperatures across most of China are moderate and the temperature difference between day and night is large, making it another golden season of the year for orchid growth. Comprehensive fertilization based on the actual condition of the orchid plants is very necessary. For robust orchid plants, apply more phosphorus and potassium fertilizer to enhance their cold resistance and lay a solid foundation for early and strong sprouting next year; for orchids sprouting autumn shoots, apply more organic fertilizer with a complete range of nutrients to meet the various nutritional needs of orchid growth and help them grow strong before winter arrives. In principle, however, fertilization should stop by the end of the month.

Let the orchids bathe in sunlight

This month includes the two solar terms Cold Dew and Frost's Descent. The sunlight is soft, so no shading is needed during the day, and the orchids can safely receive full-day sunlight, which is greatly beneficial for promoting orchid growth, strengthening the plants' resistance and helping them overwinter safely.

Increase the humidity of the orchid room

This month has little rainfall and relatively low air humidity, and the potting medium dries out very easily, so attention should be paid to increasing the air humidity of the orchid room to prevent orchid leaves from developing withered tips and scorched ends. In areas with good air quality, orchids can be left to be rained on during autumn rain, but during continuous rainfall they still need to be covered. Never let the orchid plants be rained on for long periods, to prevent waterlogging, root rot and the growth of black spot disease on the leaves.

Watch out for extreme weather and prevent frost

If extreme weather occurs in the latter part of this month, early frost may arrive in Jiangnan, and temperatures in the northern temperate zone and high-cold regions may sometimes drop below 0°C. Those who grow orchids outdoors should pay attention to weather forecasts and be ready at all times to prevent frost and freezing damage.

Combine repotting and division with orchid trading

Most orchid plants mature this month, making it the best time of the year to introduce varieties and to repot, divide and change the medium. If a full pot of mature orchid plants needs repotting, this work is best completed before the end of the month; if the new growth has not yet fully matured into plants, it is best to postpone repotting and division to allow continued growth, and wait until next spring to divide the pot. Introducing plants is the first step in orchid growing, and getting a good start is crucial, but the following issues must be noted. First, strictly control quality and do not introduce diseased plants. Orchid growers need to keep their eyes open when introducing plants and, following the principle of quality first, shut out diseased orchids. Orchid plants are divided into strong, medium and weak plants, with large price differences. Growers with solid skills can appropriately introduce small and medium plants to grow, which both saves money and improves their own cultivation skills; beginners are best off introducing highly adaptable native species and vigorous strong plants. Although the price is higher, they are relatively easier to grow. Second, strictly control the environment and improve the success rate. Introducing orchids must take the growing environment into account, as this has a considerable impact on the success rate after introduction. Growers with modern orchid-growing facilities and superior conditions can boldly introduce greenhouse plants; growers with simple facilities are best off introducing from growers with a similar orchid-growing environment, as the chance of success is greater. Generally speaking, introducing orchids grown on a home balcony is the safest, as they are the most adaptable and have the highest success rate. Third, strictly vet the grower and ensure the goods are genuine and fairly priced. The ranks of orchid growers are a mixed lot, and to avoid being cheated, it is best to go in person to well-known, trustworthy growers to buy. Although the price is higher, the goods are genuine. Never seek cheap bargains from shady, unscrupulous dealers whose background you do not know, lest you be cheated and lose everything.

Thin the buds to promote vigor

This month, most full pots of vigorous strong plants have produced buds. Buds should be appropriately thinned on the principle of removing weak ones and keeping strong ones. Flower buds sent up by old plants should all be removed, and among the excessive buds sent up by the front leads, only the strongest should be kept while the rest are also removed, so as to help the flowers open properly next year.

Key management points for flower cultivation in December

Key management points for flower cultivation in December
1. Sowing
Flower species that can be sown in the greenhouse in December include: gloxinia, asparagus fern, clivia, tuberous begonia, cyclamen, winter coral, African daisy and so on; trees and shrubs that can be sown outdoors immediately after collection or stratified in sand to promote germination include: rose (such as 'Elizabeth'), nandina, Ardisia crenata, holly species, firethorn, palm, privet, camphor tree, small-leaf privet, soapberry, photinia, Photinia davidsoniae and so on.

2. Cuttings
Woody ornamental flowering trees and shrubs that can be propagated by cuttings in the open ground in December include: plum blossom (mainly cultivars such as 'Gongfen' and 'Lüe'); rose (mainly easy-to-root cultivars such as 'Elizabeth', floribunda rose and miniature rose); red-leaf plum, wintersweet (cutting with a heel), spiraea, boxwood species and so on. Among these, plum blossom and red-leaf plum cuttings should use yellow-heart soil, rose cuttings should use a mixed medium of rice-hull ash and fine sand at 2:1, and other species can use ordinary sandy loam, covered with plastic film to retain warmth and moisture.

3. Grafting
Fine plum blossom cultivars such as 'Guhong' and 'Zhusha' can be grafted in December using seedlings of apricot, fruiting plum, peach and so on sown that year: dig up the rootstock, then use cleft grafting or cut grafting, then plant at a certain row and plant spacing in the seedbed, burying soil up to above the graft union, even covering most of the scion, taking care not to let water seep into the union when watering, and covering with plastic film to retain warmth and moisture; in the following spring, after the scion sprouts, remove the covering film. Using dug-up wild rose plants, bud-graft fine rose cultivars; or use healthy branch sections of the 'Elizabeth' rose cultivar (10 to 12 cm long), cut-graft or cleft-graft fine rose cultivar scions onto the upper end, then plant the grafted 'Elizabeth' branch sections into a loose seedbed. The graft union can be buried together in sandy soil, taking care not to let water seep into the union when watering, and covering with plastic film to retain moisture and warmth; in the following spring, after the scion sprouts, remove the covering film, and only after it has fully survived may a blade be used to cut the binding tape at the union. In addition, red maple can be side-grafted indoors with a bag over it to retain moisture.

4. Layering
Trees and shrubs that can be propagated by layering in December include: Podocarpus, plum blossom, camellia, osmanthus, Michelia figo, Chaenomeles speciosa, purple magnolia, snowball viburnum, weigela, gardenia, winter jasmine, forsythia, hydrangea, Stephanandra incisa, Viburnum macrocephalum, Spiraea thunbergii, pomegranate and so on.

5. Division
Herbaceous flower species that can be propagated by division in December include: rain lily, dwarf lilyturf, Reineckea carnea, hosta, Hosta ventricosa, red-flowered oxalis, Aspidistra, Cymbidium ensifolium, Cymbidium goeringii, Cymbidium faberi, sword fern, blackberry lily, iris, big-leaf lilyturf, Ophiopogon, Rohdea japonica, mother of thousands, Aglaonema. When cutting off offsets from the base of a large variegated bromeliad plant, the small plants must already have grown on the mother plant for three or four months; otherwise the colored bands on the separated offsets tend to disappear, which deserves special attention.

6. Collecting seeds
The herbaceous flower seeds that can be collected in December are generally those of herbaceous flowers moved into the greenhouse or cold frame, such as salvia species, globe amaranth species, marigold, French marigold, cyclamen, clivia and so on. Clivia seeds are best sown immediately after collection.

Key points of month-by-month cultivation and management techniques for orchids

January

Preventing freezing is the first priority. This month includes the two solar terms Minor Cold and Major Cold, and in China, apart from the tropical and subtropical regions, the monthly average temperature is below zero. As cold air from the north keeps moving south, this month is the coldest period of the year; in China's tropical regions there are records of extreme minimum temperatures of minus one degree. Orchid management should put freeze prevention first. Once a cold wave strikes, windows should be kept tightly closed morning and evening, ensuring the orchid pots cannot suffer freezing damage. If the orchid room temperature falls below zero, heating can be added, but note that the heating temperature must not be too high; about 5 degrees at night and about 10 degrees during the day is suitable. At the same time, note that coal stoves must not be used for heating, to prevent coal gas from harming the plants.

Let the orchids fully receive light, and pay attention to ventilation. The sunlight this month is soft, so the orchids can safely receive full light. On clear days, if the orchid room temperature is around 10 degrees, windows can be opened during the day for ventilation, but at night doors and windows still need to be closed promptly.

Temperatures are low this month, so watering should be done in the morning on clear days, keeping the water temperature as close to the air temperature as possible. Never water into the flower buds, to prevent the buds from rotting.

February

Watch the weather and guard against freezing damage. This month includes the two solar terms Start of Spring and Rain Water. Although the temperature this month is slightly higher than last month by 1-2°, in China, apart from the tropical and subtropical regions, the monthly average temperature is still below zero, cold waves still strike from time to time, and the weather is still very cold. Orchid care is still mainly about preventing freezing.

Remove weak buds and keep strong ones, and thin the buds appropriately. After a winter of dormancy, the flower buds begin to grow faster. Orchid growers should, according to the vigor or weakness of the potted orchids, follow the principle of removing weak buds and keeping strong ones, and promptly thin the buds that newly emerged after the Start of Winter and those produced by the back leads. Generally, for a full pot of vigorous Cymbidium goeringii, keep 2-3 flower buds, and for Cymbidium faberi, keeping one flower bud is enough. This allows nutrients to be concentrated, which helps the orchids open properly.

Appropriately spray foliar fertilizer. As the earth returns to spring, orchid buds begin to stir, and extremely dilute fertilizer can be applied, but organic or inorganic fertilizer must not be applied to the roots. Foliar application of inorganic fertilizer or biological bacterial fertilizer should still be the main approach, to promote the vitality of new buds and ensure the nutritional needs of new bud growth.

Clean the orchid room, kill insects and sterilize. Dead branches, fallen leaves and scorched leaf tips should be cut off promptly, and orchid-growing tools and the orchid garden should be thoroughly treated with insecticide and disinfection. When spraying chemicals, note three points: first, the solution must not be too concentrated, to avoid harming orchid buds; second, spraying should be done on clear mornings; third, the amount of chemical must not be sprayed too heavily, to avoid it pouring into the leaves and rotting the heart.

March

Before the flower stalk shoots up and blooms, full light is suitable; when the flowers open, shade is needed. This month includes the two solar terms Awakening of Insects and Spring Equinox. In China, apart from Heilongjiang province and the high-cold regions of Tibet, the average temperature is above zero, the weather gradually warms and the sunlight is soft. Orchids that have formed buds should be placed in a sunny spot to receive full light before blooming. After the flower buds begin to shoot up, they must be appropriately shaded; otherwise the petals easily turn yellow in color, and the lips of solid-colored petals turn white or slightly yellow, damaging the flower's appearance and affecting flower quality.

Keep moisture appropriate, water cautiously; when the flowers are open, the potting soil should be on the dry side and the air humidity should be high. This month Cymbidium goeringii is in full bloom, and the air humidity should be somewhat higher. Air humidity greatly affects the length of Cymbidium goeringii flower stalks; the effect is most pronounced on lotus-petal Cymbidium goeringii. Although air humidity should be high during orchid blooming, potting soil moisture should not be too high and should be appropriately on the drier side. For standard petal-type flowers, just before the buds open and the petals shoot up, the potting soil should be appropriately controlled for moisture, watering less so the potting soil is slightly dry. But for strange-flower type orchids, when the flowers are open the potting soil must not be too dry; on the contrary, it should be a bit more moist, so as to fully display the elegance of the strange flowers.

Cut the flowers appropriately to avoid excessive nutrient consumption. Orchid blooming consumes the most nutrients, and if the flowers are left to bloom and fade freely, it harms the orchids' later growth, so the flowers need to be cut at the right time. For Cymbidium goeringii, generally after full bloom the flowers should be cut after about half a month; for multi-flowered types on one stem, they should be cut five or six days after the top flower has fully opened. If it is a rare famous variety or the pot has few plants, the flowers should be cut immediately two or three days after opening.

April

Open windows for ventilation, and move plants out cautiously. This month includes the two solar terms Clear and Bright and Grain Rain. The weather is warm, and frost and snow have basically stopped. Apart from extreme cold wave weather, all potted flowers can be moved outdoors for care. For orchids grown in enclosed orchid rooms, windows should be appropriately opened to allow ventilation.

Sterilize and kill insects; orchids in bloom need shading. This month orchids can receive full light, and generally no shading is needed. This month Cymbidium faberi begins to bloom in full, and during blooming it should be shaded; otherwise the flower color is poor and flower quality is affected. As temperatures gradually rise, pests and diseases begin to breed, so orchid rooms and orchid plants should promptly be treated with fungicides and insecticides for sterilization and pest control.

Repot and divide to promote growth. Spring is one of the best seasons for repotting and dividing orchids. If a potted orchid's plants have filled the pot, or the potting soil has not been changed for more than two years, spring should be used to promptly repot or divide it.

Withhold water and fertilize to promote strong shoots. For potted orchids that have not produced flower buds, a light fertilizer can be applied around the Spring Equinox and Clear and Bright. For potted orchids that have finished flowering, fertilizer must be applied only after a post-bloom rest period of about ten days. Whether fertilizing potted orchids that have not bloomed or those that have finished blooming, it is best to choose clear weather, and before fertilizing, water should be appropriately withheld once; fertilizing when the potting soil is on the dry side gives the best results. This way, on the one hand the orchid roots and potting soil absorb fertilizer fully, and on the other hand it also stimulates the orchid plants to sprout strong shoots, with good results.

May

Use sparse netting for shading. This month includes the two solar terms Start of Summer and Grain Full. Temperatures gradually rise and sunlight gradually strengthens, so orchids grown outdoors can be appropriately shaded with sparse netting.

Fertilize to strengthen shoots. This month most orchid shoots have broken through the soil. To make the new shoots grow strong, orchids must be given supplementary fertilizer, preferably a dilute organic fertilizer applied to the roots, best done in the evening, with a "reviving water" watering the next morning. Foliar fertilization can also be used, spraying with one-thousandth urea plus one-thousandth monopotassium phosphate; to prevent fertilizer damage, spray water the next morning to wash the leaves. Biological bacterial fertilizers can also be sprayed, such as root-promoting agents, plant nutrients, orchid bacterium king, Xishuo and so on. When growing orchids with granular medium, it is best to alternate organic fertilizer, inorganic fertilizer and biological bacterial fertilizer, once a week.

Water cautiously to prevent shoot rot. When orchid shoots break through the soil, open their mouths and spread their leaves, the shoots should be covered before watering, to prevent water accumulating in the shoot heart and rotting the shoot and causing disease; if orchid shoots accidentally get water in them, use a toothpick wrapped in toilet paper to absorb the water dry, to eliminate future trouble.

Pay attention to preventing pests and diseases. This month, due to damp shade and gradually rising temperatures, insects and fungi breed, making pest control and sterilization work very important. Spray fungicide once every ten days, alternating thiophanate-methyl, carbendazim, copper hydroxide and so on to improve efficacy. Spray insecticide once every half month, mainly omethoate and dicofol, which are most effective at killing scale insects and red spiders.

June

This month includes the two solar terms Grain in Ear and Summer Solstice. This month has the longest daytime hours of the year, with high temperatures, strong light and muggy weather, so shading and ventilation work must be done well to avoid sun scorching and burning orchid leaves.

This month Jiangnan is in the plum rain period, with large rainfall, and rainfall elsewhere also gradually increases. In places where air pollution is not serious, orchids can be left to be rained on during light and moderate rain, but during heavy rain and rainstorms it is best not to let them be rained on, to avoid waterlogging, root rot and shoot rot. During the plum rain period air humidity is high, so watering should be reduced.

This month is the orchid sprouting and leaf-spreading period, which requires a relatively humid environment. If the potting soil is too dry and air humidity too low, it easily causes stalled buds and shrinkage of orchid root growth points, which is very unfavorable to orchid growth. Orchid management during the bud period should emphasize the word "moist," striving to create a relatively moist environment for the orchid-growing site and potting soil. After the plum rain, when the climate is dry, the relative air humidity during the day can be kept no lower than 40% through various means such as sprinkling water in the orchid garden, spraying water on the leaves, increasing humidity with water trays and humidifiers. On the premise of ensuring the potting soil is air-permeable and drains well, watering can be appropriately more frequent, keeping the potting soil relatively moist, to ensure orchid buds sprout, emerge and spread leaves and grow strong.

July

Make heat prevention, shading and cooling a priority. This month includes the two solar terms Minor Heat and Major Heat, with a monthly average temperature of around 30°, making it the hottest month of the year, with unbearable heat. Because the weather is extremely hot, shading, ventilation and cooling work must be strengthened; in muggy weather, exhaust fans, mini electric fans and so on can be used to stir a light breeze and promote air circulation. At the same time, sprinkle water on the ground frequently to cool it down and prevent the severe heat from harming the orchids.

Water cautiously to prevent shoot rot. Temperatures are high this month, so watering should generally not use the soaking-pot method or the overhead watering method; spray and mist as little as possible, to avoid water pouring into the leaf heart and causing rot. In the high-temperature season, the potting soil must not stay wet for long, to prevent root rot, stem rot, soft rot and shoot rot. Water management is the focus of this month's work.

Apply fertilizer slowly. This month is hot, and orchids enter dormancy, so root application of organic or inorganic fertilizer is prohibited. For fertilization, foliar spraying is better, using one-thousandth urea plus one-thousandth monopotassium phosphate or biological bacterial fertilizer alternately, to supplement nutrients, promote vigorous growth and lay the foundation for sprouting and flowering next year. Generally speaking, spray in the evening and wash the leaves the next morning, to prevent fertilizer remaining on the leaves from being exposed to high temperatures and sunlight and harming the plants.

Promptly prevent and control pests and diseases. This month is when various pests and diseases are most likely to occur, so sterilization and pest control work cannot be relaxed. To prevent and control pests and diseases, spray chemicals alternately, to prevent orchid plants from developing resistance and reducing the effect. Apply chemicals on a cool evening, and do not make the solution too concentrated, to prevent chemical damage.

Reinforce the orchid room and guard against rainstorms and typhoons. This month rainstorms, typhoons and other extreme weather occur frequently in various places, so preventive work must be done well, taking reinforcement and rain-shelter measures to prevent fierce winds and rainstorms from knocking over pots and breaking orchid leaves.

August

Prevent heat and cool down. This month includes the two solar terms Start of Autumn and End of Heat, with a monthly average temperature similar to last month and extremely hot weather, making it the second high-temperature month of the year. Pay attention to preventing heat and cooling down, and ensure ventilation.

Water promptly to avoid "water-chestnut-shell dryness." In the golden autumn season, with high clear skies, light clouds and bright sunlight, evaporation is high and the potting soil easily dries upward from the bottom of the pot, forming "water-chestnut-shell dryness," which affects flower bud development and harms orchid roots. Measures such as increasing humidity with water troughs, sprinkling water on the ground and humidifiers can be taken to keep the relative air humidity no lower than 40%. To avoid "water-chestnut-shell dryness," orchid growers must frequently observe the wetness of the potting soil; when the potting soil is found to be on the dry side, water thoroughly in good time, keeping the soil moist but not waterlogged, and never let the potting soil become too dry.

Proceed from reality in everything and let the orchids receive more light. After the middle of this month, the degree of shading should be reduced as much as possible according to the orchid-growing environment. Apart from orchids grown in courtyards and on rooftop platforms, which need appropriate shading, orchids in other growing sites can boldly receive full light, especially full pots of vigorous strong plants. At night, the sliding windows of the orchid room should be opened as much as possible to allow full ventilation, maximizing the day-night temperature difference.

Fertilize to promote vigor and buds. From the middle and latter part of this month, root-apply organic fertilizer to vigorous Chinese orchid seedlings, or apply foliar fertilizer; the two can be alternated. Fertilization should appropriately increase the phosphorus and potassium components, to help produce flower buds while ensuring autumn shoot growth and the development of strong early-spring shoots. Fertilization is best done dilute and on clear evenings, with "reviving water" watering the next morning, to prevent fertilizer damage.

Prevent extreme weather. This month typhoons sometimes strike the Jiangnan coast, and other regions also often have rainstorm weather, so the orchid room should be reinforced and work to prevent typhoons and rainstorms done well.

Do not relax pest and disease control. This month pests and diseases are rampant, and it is a high-incidence month for soft rot, stem rot and other pests and diseases, so pest control and disease prevention work must be done well. Sterilization and pest control are best done on clear evenings as the sun is about to set; spray both the orchid leaves and the whole orchid garden.

September

Remove shading and give full light. This month includes the two solar terms White Dew and Autumn Equinox, with a monthly average temperature of around 25°. The summer heat gradually fades and the sunlight becomes increasingly soft, so according to the orchid room's situation, the orchids can be given as much sun as possible to strengthen their resistance to pests, diseases and winter cold. From the latter part of the month, shading work can basically be ended.

Increase humidity and avoid dryness. The autumn climate is dry, so the ancient teaching "autumn must not be dry" should be followed, and attention should be paid to increasing air humidity to avoid "water-chestnut-shell dryness." Measures such as increasing humidity with water troughs, sprinkling water on the ground and humidifiers can be taken to keep the relative air humidity no lower than 40%. Frequently observe the wetness of the potting soil; when the potting soil is found to be on the dry side, water thoroughly in good time, keeping the soil moist but not waterlogged, and never let the potting soil become too dry.

Sterilize and kill insects. This month scale insects, red spiders, aphids, slugs and snails are rampant, and soft rot and black spot disease occur frequently, so pest control and sterilization must be timely and the drug varieties rotated regularly; the orchid site can be fully disinfected 1-2 times. The best time to apply chemicals is still the evening, which helps enhance the sterilization and pest-killing effect.

Repot and divide. After the Autumn Equinox solar term, with clear autumn skies and crisp air, it is a great time for repotting, changing the medium and dividing plants. Any orchid needing repotting or division can be promptly handled during this period according to the essentials of repotting and division.

Identify buds to recognize orchids. This month flower buds begin to break through the soil, so observe and identify the color, veins and shape of various flower buds to strengthen the ability to distinguish different varieties. If the aim is propagation, so as to send more new and strong shoots next year, the flower buds can be removed.

Fertilize according to the plants. This month is the last period for orchid fertilization. For vigorous large and strong plants, apply fertilizer appropriately to guarantee large shoots and large plants next year; but for diseased and weak plants, generally do not fertilize, and clean cultivation is better. For fertilization, root application and foliar application can be done in turn, and organic fertilizer, inorganic fertilizer and biological bacterial fertilizer used alternately.

October

Let the orchids bathe in sunlight. This month includes the two solar terms Cold Dew and Frost's Descent. With clear autumn skies and crisp air and soft sunlight, shading work is declared over, and the orchid plants can receive sunlight all day, promoting orchid growth and full flower buds and strengthening resistance to disease and cold, which helps the orchid plants overwinter.

(2) Increase the humidity of the orchid room. This month has little rainfall and relatively low air humidity, and the potting medium dries out very easily, so attention should be paid to increasing the air humidity of the orchid room to prevent orchid leaves from developing withered tips and scorched ends. During autumn rain, orchids can be left to be rained on, but during continuous overcast rain they still need to be covered. Never let the orchid plants be rained on for long periods, to prevent waterlogging and root rot, otherwise black spot disease easily occurs.

Apply more phosphorus and potassium fertilizer. October temperatures are moderate, making it another golden season for orchid plant growth, so apply more phosphorus and potassium fertilizer in good time to meet the various nutritional needs of orchid growth, so they can grow into large, strong plants before dormancy, laying a solid foundation for early and large sprouting next year and helping them overwinter and enhancing cold resistance. But by the end of the month, in principle, the year's fertilization work should end.

Prevent frost. In the latter part of this month, early frost may arrive in Jiangnan, and temperatures in the northern temperate zone and high-cold regions may sometimes drop below zero. Pay attention to weather forecasts and do a good job of preventing frost and freezing damage.

Repot and divide at the right time. Most orchid plants mature this month, making it the best time of the year to exchange and introduce varieties and to repot, divide and change the medium. If repotting is truly needed, this work is best completed before the end of this month; if the new growth has not yet fully matured into plants, it is best to postpone repotting and division to allow the new growth to continue growing, and there is no harm in starting next spring.

November

Do a good job of freeze prevention. This month includes the two solar terms Start of Winter and Minor Snow, and winter begins to set in. This month early frost gradually arrives in Jiangnan, so frost prevention work must be done well; the north sometimes has strong cold waves, with low-temperature frost occurring. From the end of this month, the severe winter begins, so winter cold-prevention preparations must be made well. Pay attention to weather forecasts and take protective measures promptly to avoid freezing damage.

Clean the orchid room, disinfect and sterilize, and proactively prevent orchid pests and diseases. In winter, temperatures drop noticeably, orchid vegetative growth ends and the plants shift to the reproductive growth stage. After the Start of Winter, before temperatures drop to zero, choose clear weather to carry out a thorough cleaning of the orchid room, removing all kinds of dirt and clutter and ensuring no hygiene blind spots are left, and carry out a comprehensive sterilization and disinfection of the orchid room and orchid plants, to minimize or eliminate the occurrence of various pests and diseases, which will surely achieve twice the result with half the effort.

Give full light, temper the orchid plants, and accumulate energy for next year's flowering and sprouting. Winter is the reproductive growth season for Chinese orchids; flower buds grow slowly and new shoots are also developing, so full light is especially important. Winter sunlight is soft, so whether orchids are grown on a balcony, in a courtyard or in a dedicated orchid room, the shading facilities should be promptly removed, letting the orchids boldly and fully bathe in sunlight, to accumulate the energy needed for next year's flowering and sprouting. If the orchid-growing site has insufficient sunlight in winter, biological growth-regulating lamps should also be used to supplement light for the orchids; otherwise it directly affects orchid flowering and sprouting.

This month repotting and plant introduction can still be done. Those who have not yet completed repotting work need to finish it promptly in the first and middle ten days of the month, which helps the orchid plants recover and helps them sprout early and strongly next year.

December

Freeze prevention should be put first. This month includes the two solar terms Major Snow and Winter Solstice. In China, apart from the tropical and subtropical regions, the monthly average temperature is below zero, and freeze prevention is the focus of orchid care this month. When the weather is cold, close the windows; the night temperature is best kept at around 5°, not below 0°, and the daytime temperature is best kept at around 10°. If the orchid room temperature falls below zero, heating measures must be taken; water radiator heating is best, and electric heaters or air-conditioning heating are also acceptable, but coal stoves must absolutely not be used to heat the orchid room, to prevent the orchid plants from being poisoned.

Give full light and pay attention to ventilation. This month the orchids can safely receive full light, but the orchid room needs ventilation. Although morning and evening temperatures are not high in winter orchid growing, on clear days the temperature in an enclosed orchid room can sometimes reach around 20 degrees; if ventilation is poor, the orchids suffer from stuffy heat, and spots easily form on the leaves. Once infected, they often recur the next year, affecting orchid growth. Therefore, in winter on clear days, if the temperature exceeds 10 degrees, windows must be appropriately opened for ventilation, especially from 11 a.m. to 3 p.m., to avoid the harm of stuffy heat to the orchids.

Give full vernalization. For Cymbidium goeringii, Cymbidium faberi, Cymbidium tortisepalum and Cymbidium tortisepalum var. longibracteatum that already have flower buds, in winter it is best to place them on a north-facing balcony or use temperature control measures to let them fully vernalize for more than 1 month, with the temperature generally not exceeding 10 degrees during the day and morning and evening temperatures not lower than zero; otherwise, if the temperature is too high, it is unfavorable for next year's flowering and flower quality.

Water cautiously to prevent root rot. Winter temperatures are low, water evaporates slowly and orchid roots have relatively weak water-absorbing ability, so watering should be reduced. In winter, orchid watering is best done at noon when temperatures rise, as this keeps the water temperature close to the potting soil temperature and can also avoid diseases caused by too great a difference between water temperature and potting soil temperature. If using traditional orchid-growing methods, water along the edge of the pot, which lets the soil become moistened slowly and is more conducive to the orchid roots absorbing water. For pots with bricks placed under them, the part of the orchid pot below the bricks can also be soaked in water at the right time, to let moisture rise and keep the potting soil slightly moist, with good results.

Strictly prohibit fertilization. This month orchids are dormant, so root application of any fertilizer is strictly prohibited. On clear days at noon, 1-2 foliar fertilizer applications can be appropriately given, mainly phosphorus and potassium fertilizer, which helps improve the orchid plants' cold resistance and vigor.

Summarize experience and improve orchid-growing skills. In light of the orchid plants' growth over the past year, conscientiously summarize successful experience and identify lessons from successes and failures, continuously improving orchid-growing skills.

Responsible editor: Yuanyuan