Winter Bonsai Making Methods and Picture Appreciation, Light Up the Winter Garden
Light Up the Winter Garden: Winter Bonsai Making Methods, Bonsai Picture Appreciation
Inthe cold winter, not all plants enter a dormant period. Wintersweet blooms through the snow, pines and cypresses stay evergreen all year round, and countless beauties lie hidden among the shrubs. As long as you are willing to discover them and get hands-on, winter bonsai is in no way inferior to the bustling world of summer.
Light Up the Winter Garden: Winter Bonsai Making Methods
——————————————————————————————————————————————
·Dogwood branches ·Dwarf Japanese cypress ·Black hellebore
——————————————————————————————————————————————
·Fire-colored dogwood branches ·Corokia ·Purple kale ·Coral Bells "Creme Brulee"
·Euphorbia "Blackbird" ·Golden sedge ·Scottish moss
——————————————————————————————————————————————
·Redtwig dogwood ·Sphagnum moss ·Pine cones
——————————————————————————————————————————————
·Dogwood branches ·Yin (moss) ·Black mondo grass ·Pine cones
——————————————————————————————————————————————
·Wooden bamboo stakes ·Yin (moss) ·Spicebush ·Coral Bells "Obsidian"
——————————————————————————————————————————————
·Phormium ·Moss-covered branches ·Sphagnum moss ·Hen and chicks
——————————————————————————————————————————————
·Red and yellow decorative branches ·Dwarf Japanese cypress ·Coral Bells ·Leatherleaf sedge ·Black mondo grass
" Postscript:When making winter bonsai, pay attention to the matching of texture, color, height and so on among the selected plants. There should be base plants and accent plants, each playing its own role. Of course, the most important thing is that you must make sure these plants can tolerate the low temperatures of your region.
【Related recommendations】
·How to grow agave, agave picture appreciation
·Bedroom? ">Is calla lily poisonous? Can calla lily be placed in the bedroom?
·Tracing "fragrance" to the spider lily: the soul returns
·How to grow canna, canna picture appreciation
·Tracing "fragrance" to the roseleaf raspberry: the flower affair is not over
Winter bonsai making methods, bonsai picture appreciation
Inthe cold winter, not all plants enter a dormant period. Wintersweet blooms through the snow, pines and cypresses stay evergreen all year round, and countless beauties lie hidden among the shrubs. As long as you are willing to discover them and get hands-on, winter bonsai is in no way inferior to the bustling world of summer.
Light Up the Winter Garden: Winter Bonsai Making Methods
——————————————————————————————————————————————
·Dogwood branches ·Dwarf Japanese cypress ·Black hellebore
——————————————————————————————————————————————
·Fire-colored dogwood branches ·Corokia ·Purple kale ·Coral Bells "Creme Brulee"
·Euphorbia "Blackbird" ·Golden sedge ·Scottish moss
——————————————————————————————————————————————
·Redtwig dogwood ·Sphagnum moss ·Pine cones
——————————————————————————————————————————————
·Dogwood branches ·Yin (moss) ·Black mondo grass ·Pine cones
——————————————————————————————————————————————
·Wooden bamboo stakes ·Yin (moss) ·Spicebush ·Coral Bells "Obsidian"
——————————————————————————————————————————————
·Phormium ·Moss-covered branches ·Sphagnum moss ·Hen and chicks
——————————————————————————————————————————————
·Red and yellow decorative branches ·Dwarf Japanese cypress ·Coral Bells ·Leatherleaf sedge ·Black mondo grass
" Postscript:When making winter bonsai, pay attention to the matching of texture, color, height and so on among the selected plants. There should be base plants and accent plants, each playing its own role. Of course, the most important thing is that you must make sure these plants can tolerate the low temperatures of your region.
【Related recommendations】
Key points for growing cacti and succulents
Perhaps you have just grown a pot of flowers on a windowsill, perhaps you have already collected quite a few in your small greenhouse, or perhaps you have a greenhouse packed with treasures. I hope you will gain something after reading this article. The content of this article is accumulated from the growing experience of many succulent enthusiasts, and also includes some introductory materials provided by the BCSS Harrow on the Hill Branch and its affiliates. However, the copyright owner of this webpage - BCSS and its affiliates - accepts no legal liability for plant loss or personal injury suffered by readers as a result of misunderstanding this article.To get the best methods for growing cacti and succulents, please join your local Cactus and Succulent Society (cactus and succulent community), where you can get advice from others and obtain their valuable experience, especially for some varieties that are difficult to grow. There are also some experts specializing in growing certain varieties, such as Asclepiadaceae, Euphorbiaceae, Haworthia, Hoya, Mammillaria, Lampranthus, Peperomia and Sedum.
Flower pots
Two types of pots can be used, clay pots or plastic pots. In the hands of enthusiasts, both types of pots can grow flowers well; which one to use is mostly a matter of personal preference. Plastic pots are light, cheap, retain water well and are clean. Clay pots can provide stable support for large plants and can alleviate the negative effects caused by overwatering, but clay pots are heavy and require your shelving to be sturdy enough.
Many cacti and succulents only have fibrous roots and do not need standard growing pots; it is best to use half-height or shallow pots. Planting a variety with very shallow roots in a deeper pot will only be detrimental to its growth, because the soil in the lower part that the roots cannot reach will retain moisture for a long time, making the potting soil sticky and stagnant. Those varieties with tubers or taproots need deeper soil and will grow well in standard or deep pots. No matter which type of pot is chosen, there must be drainage holes at the bottom, and some broken pot pieces or clean stones should also be placed at the bottom.
For plants grown for their stems, using bonsai pots produces a very good visual effect, with thick, strange stems (caudexes or short stems) emerging from the potting soil. Finally, some cacti and succulents come from areas rich in limestone and often grow in limestone crevices. Such plants are very suitable for planting in a whole piece of travertine (a type of calcareous sedimentary rock), and the visual effect is excellent, looking just like alpine plants.
Preparing the growing medium
Various types of growing soil are available commercially, from John Innes compost to peat soil and garden compost, mixed with horticultural coarse sand of different grades to make a medium that drains easily; the amount of coarse sand added ranges from 30% to 70%. The specific ratio needs to be determined based on your own growing experience, your growing environment and the materials available to you, deciding the mixing ratio of soil, sand and coarse sand.
Peat soil is more prone to breeding root mealybugs than compost soil. Some growers feel that Lithops do not grow very well in peat-based media. I myself initially used peat soil, and now prefer a mix based on garden soil. Coconut coir is now trending toward replacing peat soil, but this medium decomposes and rots too quickly for very slow-growing cactus varieties.
Some varieties, such as Echeveria in the Crassulaceae family, do not like calcareous material and prefer media containing peat soil. Others, such as Ariocarpus fissuratus, Echinocactus horizonthalonius 'Tranquillum' and Escobaria tuberculosa, usually grow in calcareous loam in their native habitats, so some heavy calcium carbonate or dolomite granules should be added to their medium. There are also some plants such as Geohintonia that like to grow in almost pure gypsum soil.
Heavy calcium carbonate is weakly alkaline and can neutralize acidity in the soil.
Dolomite contains calcium magnesium carbonate and is weakly alkaline.
Gypsum consists of calcium sulfate and is neutral.
Quicklime consists of calcium oxide; its alkalinity is too strong and it cannot be used for potted flowers.
The medium I (the author) personally use:
For example, the potting mix I use is made by composting kitchen organic waste and garden leaves and other waste, then sifting out the fine particles. I accumulate this waste in a large plastic barrel 4 feet high, let it rot and decompose, and even made some pocket money selling it to the local enthusiasts' association. Unlike peat soil, this homemade compost medium contains almost no soil and is not conducive to the breeding of pests such as root mealybugs.
After the compost is sifted, add one third sand, where the sand is made by mixing equal amounts of pure sand and 2 mm diameter flint or quartz coarse sand. I also use this coarse sand to decorate the surface of the potting soil. The ratio can be measured using a small container on hand or by hand, so my mix ratio is four handfuls of compost soil, plus one handful of coarse sand and one handful of pure sand. For varieties whose native soil is alkaline calcareous soil, I add some dolomite granules, and for "difficult" varieties, I usually add more sand.
Put the mixed medium into a stainless steel container, pour in rainwater to moisten the soil, then seal the container and heat it over fire for some time (such as 2 hours at 107°C) to ensure the killing of insects, larvae, eggs and weed seeds inevitably contained in garden waste compost, but some beneficial soil microorganisms will survive, especially those that reproduce by spores.
Repotting spiny plants
Ideally, plants should be repotted once a year to provide them with fresh, nutritious potting soil and growing space. While repotting, you can also check root growth and whether there are pests such as root mealybugs.
When repotting spiny cactus globes, to prevent the spines from breaking, a good method is to wrap them in a layer of newspaper or soft paper towel, then secure it with a rubber band or string. If the paper becomes tangled with the long spines when opening it, wetting the paper makes it easier to remove, and small paper scraps can be removed with tweezers. "Old hands" can repot directly with bare hands, letting as many spines as possible contact the palm evenly to distribute the plant's weight, but bare-handed handling is not recommended for Opuntia plants, because the tips of their fine spines (glochids) break off after piercing the skin, and bare-handed handling is also not recommended for Mammillaria plants with hooked spines.
When repotting, after turning the plant over, tap the edge of the pot lightly against the corner of a chair, or use a piece of wood to tap the edge of the pot to separate the pot from the soil. When the above methods are not very successful, inserting a wooden stick into the hole at the bottom of the pot and applying even pressure can help, but be careful not to do this with plants that have fleshy roots or tubers if possible. If it is a plastic pot or another flexible pot, gently squeezing the potting soil through the pot wall first will make it easier to remove the pot. Finally, if the root ball is too tight and nothing else works, in order not to harm the plant, you can break the pot, which is better than injuring the plant.
Set the pot aside, remove the old soil from the plant's root system, and pay attention to whether there are pests. When removing old soil, use a small thin stick or a slender label card to probe carefully. If there are white fluffy small clusters or tiny insects in the soil, shaped like woodlice and 2 mm long, they are root mealybugs. Once pests are found in the soil, remove as much old soil as possible, or wash the soil away with water, and soak with a systemic insecticide, preferably one containing dimethoate.
Replant the plant into a pot. If the plant's root ball has already filled the old pot, change to a slightly larger new pot (about 2 cm larger in diameter). Fill the dry new medium evenly among the roots, and after planting, leave it for about two weeks before watering, to help the root wounds heal.
A note on growing Euphorbia
The genus Euphorbia includes a large number of fascinating succulent and non-succulent plants, with extremely varied forms and sizes, and they are very worth collecting. But one common feature of Euphorbia plants is that the stems and leaves contain milky sap, which is highly toxic, so you must be careful when caring for them. Never let Euphorbia sap accidentally get into your eyes, and if it touches the skin, wash it off immediately with clean water. Washing your hands after repotting Euphorbia plants or doing routine care is a good habit worth encouraging.
Light
Most cactus globes and succulents like as much light as possible. A south-facing or southeast-facing windowsill, greenhouse, cold frame or glasshouse is the most ideal environment. The varieties suitable for these growing environments depend on whether their minimum overwintering temperature can be met. Plenty of sufficient light can prevent plants from becoming "leggy" and promote flowering. Although the natural growing environment of cactus globes has strong light, they can also adapt to the low-light climate of the UK, so after a long, dark winter, when welcoming the first rays of sunlight in the new spring, prevent the plants from getting sunburned while sunbathing. Newly purchased plants, or plants that have been growing in shaded environments or dark corners of a greenhouse, should have light intensity gradually increased over several days until they finally adapt to full-sun conditions.
Light and temperature for cacti and succulents that bloom at Christmas
The formation of flower buds in Schlumbergera/Christmas cactus is affected by day length and temperature. A day length of less than 12 hours promotes flower bud formation, and short days must also be combined with low night temperatures (such as 4.5-18°C). After suitable natural or artificial short-day conditions are met, flower buds will appear in about 10-20 days. Once buds appear, day length no longer has any effect on flowering (though it cannot be ruled out that too weak light may cause bud drop). Of course, day length will affect a possible second wave of flower buds. Flowering generally occurs in the 7th-8th week after flower induction, which means that to make the plant bloom at Christmas, flower induction should be started on the eve of Halloween (October 31). Flower induction can be done by artificially reducing light under normal daylight; for example, a "5-foot candle" is enough, meaning the use of artificial indoor light. But based on my experience with some plants grown in the living room, most varieties are not like Euphorbia plants (such as Poinsettias), which are very sensitive to brief artificial light, so the flowering period is very likely to be from mid-November to March and cannot be very precise. However, because the daylight in the UK in autumn and winter is too dark, plants may not be able to store enough energy to flower, so I increase the light intensity for plants receiving timed artificial lighting.
Some newly introduced multi-colored hybrids (such as Gold Charm) have flower colors that are "temperature sensitive." When the temperature is below 15.5°C, the flowers are pink, and the lower the temperature, the more pronounced this is. This can be very disappointing when you are hoping for brilliant multi-colored flowers. The solution is to raise the temperature of the plant's growing environment when buds appear and the buds are swelling.
It is recommended to stop fertilizing 3-4 weeks before flower induction begins, and afterward water only with rainwater.
Causes of bud drop: too high temperature, harmful gases produced by oil heating (ethylene), too low light levels, overly dry conditions, cold snaps.
Watering
Frequency: During the growing period, cacti and succulents cannot be kept dry for long periods; this is common knowledge. In hot summer, water once a week and keep the potting soil moderately moist and dry. When the weather turns cooler, extend the watering interval, and the potting soil must dry out completely before watering again. In winter, many cacti and succulents go dormant, and at this time they need only a very small amount of water, or even no water at all, but this also depends on the specific environmental temperature and light intensity. If your plants are placed on a windowsill in a heated room in winter, they should also be watered in winter.
Do not leave pots of cacti and succulents soaking in water for long periods. Too much water is the biggest cause of death for these houseplants.
Water quality: Tap water in many parts of the world contains alkaline and other saline minerals, as well as additives such as chlorine, and these should be avoided as much as possible. Directly flushing plants with tap water containing various saline minerals will leave fine deposits on their surfaces, and a layer of deposits will form on the spines at the base of cactus globes. After tap water is boiled, some minerals can be removed, but soluble components still cannot be removed.
Comparatively speaking, clean rainwater is the most ideal water. During the growing period, some fertilizer (special cactus fertilizer or balanced compound fertilizer) should be added at each watering. Rainwater can be obtained from the downpipe of the roof of a house or greenhouse.
To prevent mosquitoes and other insects from laying eggs in your rainwater barrel, add a few drops of olive oil or vegetable oil to the barrel. The oil droplets spread on the water surface to form an oil film, preventing mosquito larvae from breathing air. In summer, the oil film should be renewed every week. Light mineral oil also works, but it slightly pollutes the water.
Clean water can also be obtained from the frost of refrigerators and other freezing equipment, or collected from air conditioner condensers. If you are a super enthusiast, you can make your own solar still, which can produce several liters of water a day in hot summer. There are many designs online for homemade solar stills, and an example diagram is below.
Water obtained by reverse osmosis desalination (bottled purified water) is also a very good choice of water. However, many household water softening devices that use ion exchange resins merely replace calcium ions in the water with sodium ions. Water produced by such devices is not suitable for watering flowers; after ion exchange the hardness is reduced, but the salt content becomes greater.
South African succulents: many of these varieties (such as Lithops and Conophytum) grow in autumn and winter, and watering should take this into account.
(Translator's note: The author of this article lives in the UK, where the climate differs from our country, so the watering times for Lithops and Conophytum are not a useful reference.)
Lithops are watered normally from early summer to late autumn (late May or June to late September in the Northern Hemisphere), bloom from late August to late autumn depending on the variety, and then as temperatures drop, watering is reduced, letting their skins gradually wrinkle to a papery appearance, until normal watering resumes in early summer of the following year.
Conophytum species have a later growing period in autumn and winter and usually bloom at the beginning of the growing period. Normal watering should run from late summer and early autumn to spring, but water should be withheld during the coldest winter months. Pay attention to observing the condition of the plants; do not wait until they are almost dead from dryness to water them, otherwise they will never wake up from dormancy again.
Flowering in Aizoaceae plants is affected by day length, and artificial light may disrupt their normal flowering cycle (of course, some experts can use artificial light to simulate changes in day length and control plants to bloom at any desired time of year).
About greenhouses
Site selection
Building a greenhouse in your own garden may be the easiest point of consensus among most gardening enthusiasts and collectors of a particular variety. Ideally, a standalone, unneighbored greenhouse built for cactus globes and succulents should have its ridge line running north-south, so that it can receive maximum light throughout the year. A greenhouse with an east-west ridge can receive more sunlight in winter and is very suitable for specially growing succulents whose growing period is in autumn and winter. Whichever orientation is chosen, larger shade, nearby trees and locations with frequent strong winds should be avoided. Avoid placing the greenhouse door on the side of the prevailing local wind direction to prevent cold damage, and avoid places prone to waterlogging. The greenhouse should not be too far from the house, as this is not conducive to power supply and heating.
Construction
The greenhouse should be built on a complete foundation, or a foundation should be made specifically for it. A hard ground makes walking convenient and is less likely to breed pests. If the ground as a whole has a slight slope, it is even better for drainage; building a drain with cement is better. But if you want to plant large succulents directly in the ground, you should first build a foundation for them in the chosen positions to prevent them from falling over.
Building the frame of a greenhouse requires some prior thought; for example, should wood or metal be used? Both materials have their supporters. Wood looks more "natural" and blends more easily into the garden scenery, but it is susceptible to insect damage and rots easily in humid environments, so its lifespan is short and it requires frequent maintenance. However, if hardwood materials such as cedar are used, this problem is somewhat reduced. Aluminum alloy frames conduct heat easily, which is not good for keeping warm in winter, so they are inferior to wood in this respect, but they require little maintenance and have a long lifespan. Some new aluminum alloy profiles incorporate insulating materials.
Greenhouses generally use horticultural glass, which contains fewer coloring agents and has higher light transmittance than ordinary flat glass used in house windows. New UV-stabilized acrylic plastic panels are even better; they have lower thermal conductivity than glass and are better for heat retention. However, some types of plastic panels may release gases harmful to plants, so be sure to use models specifically designed for horticultural applications. Various double-layer panel types can also be used, but they may reduce light transmittance, and sunlight is too precious in a country like the UK. Reinforced glass with liner, often used for roof installation, also has this problem of low light transmittance.
Shelving
Greenhouse shelving can be made of wood or metal, each with advantages and disadvantages. After watering, potted plants become very heavy; clay pots gain more weight after watering than plastic pots, and media using compost soil are heavier than those using peat soil. If whole solid flat boards are used as shelf boards, pests such as mealybugs can easily migrate and infest plants. If spaced slats are used as shelf boards, air circulation is better, but pests can still migrate easily, and using pesticide mats and granular chemicals on slatted shelves is inconvenient.
Heating
There are many ways to heat a greenhouse or cold frame (hotbed) in winter. An electric fan with a heater is good, but the cost is very high, and it produces dry hot air, so on sunny days spraying water for humidity is also needed. Tubular heaters can also be used, but a device to promote air circulation must also be installed. If electric heating is used, you need to study the provisions on special taxes in Chapter 7 of the "Savings Act." Gas heating is very good, but pipelines need to be laid in advance, and installation costs are relatively high. Oil heating is also good and somewhat cheaper, but it produces an unpleasant odor, and attention must be paid to fire safety and preventing plants from being blackened by fumes.
Electric bottom heating under pots is a very efficient heating method, and there are many types of horticultural heating mats on the market. The alternative method I use is to install 8 10Ω 25-watt metal film resistors, two in series per group, under some aluminum plates on the shelving, then connect the groups in parallel and connect them to a 200-watt transformer to produce 10
- 20 V low voltage, thus achieving direct heating on the shelving. Also install a residual current circuit breaker in the circuit, especially when using metal shelving.
You cannot rely solely on under-pot heating mats to heat the entire greenhouse, because the heat from the mats acts directly on the plant roots. To maintain room temperature, excessively high heating temperatures may burn the plant roots. After plants are heated, they need to take up some water to prevent excessive dryness. If you water directly into the pots, or soak the pots, the heated shelving will produce a large amount of steam that condenses on the cold surfaces of the greenhouse.
Enthusiasts skilled in circuits often like to look for various secondhand fans in thrift stores, but they need to check their operating voltage and make sure they can use the local mains electricity to make them work safely and effectively. A not-too-large fan, if installed in the right position, can very effectively improve air circulation in the greenhouse and promote healthy plant growth.
About light and artificial lighting
Light is composed of massless particles (photons) moving at a high speed of 300 million meters per second. It takes only one millionth of a second (1 millisecond) to travel 300 meters. The amount of energy carried by a photon determines the color (wavelength) of the light.
The wavelengths of light visible to the human eye range from 400 to 700 nanometers, and the human eye is less sensitive to wavelengths closer to the limits at both ends, while it is very sensitive to wavelengths in the middle of this range. Most light sources produce mixed light composed of different wavelengths, which the human visual system perceives as various different colors.
Specific wavelengths or combinations of specific wavelengths form various specific colors. Yellow light is formed by light with a wavelength of 590 nanometers or by mixing green and red light. White light is usually formed by mixing visible light of all wavelengths from purple to red, but white light can also be mixed from the three monochromatic lights of pure blue, green and red. Most people usually cannot directly observe the continuous spectrum of various colors from white light composed of the full spectrum, but when observing a fluorescent lamp through a slit, the various color spectra can be seen.
Light intensity: The human eye often makes mistakes when judging light intensity, because the human eye has a strong ability to adapt to light intensity. In a well-lit office, the light intensity on the desktop is about 2000 Lux (lux), while direct sunlight can reach at least 8000 lux. In the tropical native habitats of many cactus globes and succulents, light intensity is even higher.
You can use a light meter to measure the intensity of light received by a surface.
About units of light
Lumen: The most commonly used unit for measuring light output power (also called luminous flux), used to indicate the power of light output by a light source.
1 lumen = 0.00146 watts
Footcandle:
An imperial unit of light intensity or illuminance, defined as: approximately the illuminance received on a one-square-foot area at a distance of 1 foot from a point light source with the brightness of a standard candle, which is 1 "footcandle."
1 footcandle = 1 lumen/square foot
1 footcandle = 10.76 lux
Lux: The metric unit of light intensity/illuminance
1 lux = 1 lumen/square meter
1 lux = 0.0929 footcandles
1 lux = 0.00146 W/square meter
Luminous efficacy: Light power divided by electrical power consumed, expressed in "lumens/watt."
Watt: The rate at which a device consumes energy; this label does not refer to the light output power of a lamp; the energy consumed by a device is expressed in watts (or kilowatts) per hour.
Color temperature: Measured in K (Kelvin), used to indicate the color quality of the light waves produced by a light source, compared to the light emitted by a "pure black body" at the same temperature. The higher the color temperature, the higher the proportion of blue light in the light waves, and the less red light at the other end of the spectrum.
Color temperatures of some common light sources
1000 K: Candle, oil lamp
2000 K: Sunrise/sunset, high-pressure sodium lamp
2700 K: "Warm white" fluorescent lamp
2850 K: Household incandescent bulb
3000 K: Studio lighting lamps, photographic floodlights
3500 K: Quartz halogen lamp
4000 K: Flash lamp, blue floodlight
4100 K: "Cool white" fluorescent lamp
5000 K: Blue flash, electric spark, average daylight
6000 K: Bright midday sun, metal halide lamp
7000 K: Lightly overcast sky
8000 K: Overcast sky
10,000 K: Hazy sky
11,000 K: Sunless blue sky
20,000 K: Shadow of a mountain on a clear day
Plant photosynthesis requires both red light and blue light, but does not need or absorb green light, which is why most leaves appear green in sunlight.
Many plants have leaves of other colors, ranging from dark red, brown, purple to even black. This is caused by the plant producing different pigments (such as beta-anthocyanins and anthocyanins) in response to environmental influences. For example, some plants produce this biochemical mechanism to filter intense tropical sunlight, or it is the extreme expression of selectively bred cultivars. These pigments can be produced alongside photosynthesis, but sometimes can only be forced to develop by exposing the plant to intense light, especially artificial light sources containing blue and ultraviolet components.
Red light is very important for plant growth; the red light component in the pigment absorption spectrum controls seed germination, root growth, tuber or bulb formation, dormancy, flowering and fruiting. Therefore, red light is very important for promoting flowering and seed production.
Blue light stimulates chlorophyll production more than light of other wavelengths, promoting thicker leaves, sturdier stems, and a more compact plant shape. Carotenoids and xanthophylls absorb blue light, promoting the dropping of old leaves and the ripening of fruit. Riboflavin absorbs violet light (adjacent to blue light), affecting the plant's "phototropism," that is, the response of leaves to the direction of sunlight.
Light sources
Sunlight:
With a color temperature of 6000oK, it is the light most beneficial for plant growth, maintaining good leaf color and promoting flowering. Plants have evolved over tens of millions of years and have already adapted to the natural light of their native habitats. The light quality, intensity and duration in a plant's native habitat are the basis for using artificial light sources when cultivating in other climatic regions.
The greatest advantage of sunlight is that it is completely free and is the cleanest energy source, but the quality and duration of natural light are greatly affected by capricious weather, altitude and the changing seasons. Changes in day length significantly affect flower bud differentiation in many winter-blooming plants, but daylight is beyond our control unless you take supplementary lighting or shading measures. Another possible side effect of sunbathing is that plants that have endured a dark winter may get sunburned or scarred in the early spring sunlight, which can be prevented by increasing ventilation and providing appropriate shade. The filtering effect of the atmosphere can remove the overly blue light components from the spectrum, so sunlight in regions near the poles, and sunlight at sunrise and sunset during the day, has a more yellow composition, because the sunlight must pass through a relatively thicker atmosphere to reach the ground.
Incandescent lamp: This most common household lighting lamp produces yellow-white light with a color temperature of 2750 -
2850°K and a large amount of infrared radiation. This lamp is very cheap, but its electrical-to-light conversion efficiency is very low, making it unsuitable for large-area lighting. Plants receiving this light for extended periods will become spindly and weak.
Quartz halogen lamp: Produces pure white light with a color temperature of 3500°K, and its spectrum contains ultraviolet components; prolonged exposure of human eyes and skin to its light can cause mild injury. It also radiates a large amount of heat in the form of infrared radiation, and leaves or other fragile things placed too close will be scorched. It is recommended not to look directly at an illuminated quartz halogen lamp without UV filtration, as its high brightness, heat radiation and ultraviolet rays can cause irreversible damage to the eyes.
Quartz halogen lamps are relatively cheap and do not require a starting circuit. Although their higher filament temperature makes them more efficient than ordinary incandescent lamps, the operating cost of using this type of lamp is higher than the new type of discharge lamps described below, and it is also unsuitable for large-area lighting. Its compact filament structure makes it easy for the light to converge in a small area, so it can be used for "spot lighting"; if fiber optics are used to conduct the light, the infrared (heat) component can be filtered out.
Metal halide (HID) lamp: Bright blue-white light produced by arc discharge, with a color temperature close to sunlight at 5000-6500°K; one of the most effective light sources for large-area lighting, its compact filament structure makes it easy for the light to converge at a single point. Plants illuminated by this type of light have a compact shape, but its spectrum lacks the red light component that is important for flowering; specially designed lamps that produce enhanced orange-red light with a 3000°K color temperature can be used. This type of lamp requires a special starting circuit; if the lamp needs to be installed horizontally, it is necessary to check in advance whether its structure can operate in a horizontal position.
Sodium vapor lamp: This type of lamp is often used for highway lighting; the light produced by low-pressure sodium vapor discharge is a single yellow light with a wavelength of 589 nanometers. This type of lamp is very efficient, but its spectrum lacks red and blue light, which is not beneficial for plant growth. It requires a special starting circuit.
High-pressure sodium lamp: Produces slightly pinkish white light through high-pressure sodium vapor arc discharge, with a color temperature of 2050°K
, an effective light source for large-area lighting; plants grow well under this light, but the color of its light will affect the ornamental effect of the illuminated plants. Standard models of high-pressure sodium lamps are said to promote flowering and seed production, and there are lamp models that produce more blue light, which can make plant form compact. However, if high-pressure sodium lamps are used to supplement insufficient natural daylight, then blue light lamp models are not needed, because natural light contains a large amount of blue light components. It requires a special starting circuit; if horizontal installation is desired, it is necessary to check in advance whether the purchased lamp can be installed horizontally.
Using metal halide lamps and high-pressure sodium lamps at the same time exactly complements each other's strengths and weaknesses, promoting normal plant growth.
Fluorescent tube: The working principle is low-pressure discharge luminescence of an argon-mercury vapor mixed gas, which can produce line-spectrum light. The ultraviolet rays produced by the discharge irradiate the phosphide coating on the inner wall of the tube, producing warm white light with a color temperature of 2700
- 3000°K, or cool white light at 4100 -
4300°K, or 5000K-6350°K "daylight"; there are various tubes specially designed for plant growth or aquarium lighting. The operating efficiency of fluorescent lamps is moderate, and they are very suitable for lighting small or low spaces, because the surface temperature of the tube during operation is relatively low. It requires a special starting circuit, but it is very easy to purchase.