How to grow orchids? A complete guide to orchid cultivation methods and precautions
Orchid, also known as Chinese orchid, terrestrial orchid, and orchid grass, is a perennial herbaceous flower with fleshy roots of the genus Cymbidium in the family Orchidaceae. It is native to China, where it is widely distributed in Yunnan, Guizhou, Sichuan, and Tibet. It is a traditional precious flower of China and also a famous flower of the world.
People have always regarded orchids as a symbol of nobility and elegance, and together with plum, orchid, bamboo, and chrysanthemum they are called the "Four Gentlemen." With its delicate fragrance and understated elegance, the orchid, together with chrysanthemum, narcissus, and calamus, is known as one of the "Four Elegant Flowers and Grasses," and the orchid ranks first among the four. The orchid is plain and unadorned, with evergreen leaves, leaves that are soft yet firm, and flowers with a delicate fragrance that carries far. It has extremely high ornamental value and is a treasure for displaying in living rooms, bedrooms, or for accenting a study or entrance hall. Below is a detailed introduction to how to grow orchids.
I. Soil selection
The soil used for orchids should be mainly humus, primarily leaf mold or mountain forest humus soil. In the south, the humus soil from the place of origin, commonly known as orchid mud, can be used; leaf mold, vermiculite, perlite, and others can also be used to artificially prepare a loose, airy, and water-permeable growing medium. Generally, a growing medium is made by mixing 8 parts leaf mold and 2 parts river sand, or 7 parts leaf mold, 2 parts perlite, and 1 part river sand, or 6 parts leaf mold (peat soil), 3 parts compost soil, and 1 part river sand thoroughly mixed. All the growing media prepared above are slightly acidic.
II. Fertilization methods
Orchid fertilization involves, first, applying base fertilizer into the growing medium, and second, topdressing during the growing period. Topdressing mostly uses liquid fertilizer or foliar fertilizer, and the concentration should be lighter than for other flowers. Orchids should have their growing medium changed once a year, and during the growing period topdressing can be applied sparingly, with attention to timing. Generally, in the growing season, a fully decomposed thin cake fertilizer water of about 15% can be applied as topdressing, or 0.1% urea fertilizer water plus 0.2% monopotassium phosphate fertilizer water, once every 15 to 20 days; from before flowering to the flowering period, 0.2% monopotassium phosphate or plant ash water can be sprayed on the leaves 2 to 3 times to promote the development of roots, stems, and flowers. Orchids have fleshy roots, so undecomposed fertilizer must not be applied, to avoid root rot.
III. Watering methods
Watering orchids should be based on the species, growth conditions, and local climate, and should achieve moist but not wet, dry but not parched; watering should not be too much or too little, and the principle of not dry in autumn and not wet in winter should be grasped. In winter, when temperatures are low, the plants are in a dormant state, so watering should be controlled, generally once every 5 to 7 days, but Cymbidium sinense, which blooms in winter, needs more water;
In spring and autumn, water once every 2 to 3 days; in summer, when temperatures are high and orchids are also in their vigorous growth period, water on average 1 to 2 times a day. When watering, be careful to prevent water droplets from splashing onto the leaves, so as to avoid black spots that affect the ornamental effect. During the orchid's growth period, water should often be sprayed on the leaves, and in summer water should also be sprinkled on the ground around the flowerpot to increase air humidity and promote the growth and development of the orchids. For water used to irrigate orchids, rainwater and snow water are best; if tap water is used, it should be stored for 2 to 3 days before use.
IV. Temperature requirements
For potted orchids in the north, they should be moved indoors around the Frost's Descent solar term when the temperature drops to 5°C, and in the early period after being brought indoors, windows should often be opened to maintain air circulation. In winter, the indoor temperature should preferably be kept at around 10°C. After Grain Rain, move them outdoors for care. The suitable temperature for orchid growth is 16 to 24°C. In winter, the indoor temperature is generally required to be relatively low, preferably 10 to 12°C during the day and 5 to 10°C at night, and the temperature and humidity must not be too high; in summer, the temperature should not exceed 30°C.
V. Light requirements
Orchids prefer shade and fear direct strong light, so shading should be carried out in spring, summer, and autumn. For growing orchids at home, in order to control the amount of light, it is best to place them on a balcony windowsill or under the eaves with bamboo blinds for shade, generally shading from 9 a.m. to before 6 p.m., and pulling the blinds open in the morning and after 6 p.m. so they receive scattered sunlight. In winter, they should be moved indoors to a place with visible scattered light, but direct sunlight should also be avoided. Among orchids, Cymbidium sinense has the strongest shade tolerance, followed by Cymbidium ensifolium, while Cymbidium goeringii and Cymbidium faberi have weaker shade tolerance.
VI. Potting methods
The environment for cultivating orchids should be well ventilated, humid, and free of pollution. The orchid pot should be a tall pot, thick at the top and narrow at the bottom, with multiple drainage holes, or with drainage holes in the pot wall. The orchid pot itself should also have ornamental value.
Because orchids grow slowly, they can be repotted once every 1 to 2 years after the flowers fade. When potting, first place about 3 cm of tile pieces, furnace slag, and the like at the bottom of the pot to facilitate drainage. Then, put in a layer of growing medium, place the orchid seedling in the center of the pot, straighten the roots, and let them spread naturally. When half the soil has been added, gently lift the orchid seedling while shaking the flowerpot so that the soil and roots are closely combined. When the soil is filled to 2 to 3 cm from the pot rim, gently press it firm with your hands. After planting, water thoroughly and place in a cool place, spraying water once each morning and afternoon, and after about 7 to 10 days move to a cool place with dappled light for care.
VII. Precautions
1. Orchids are mainly distributed in the southeast and southwest regions. They mostly grow wild in moist valleys under sparse forests and in shaded places beside rocks, so they naturally prefer a warm, humid climate and shade and moisture, require 70% to 90% shading, and are averse to high temperatures, dryness, and strong light.
2. During orchid cultivation, withered yellow old leaves and diseased or insect-damaged leaves should be continually cut off to facilitate ventilation. After flower buds emerge from the soil, one strong flower bud should be kept per plant and the rest cut off, so as to avoid consuming too many nutrients and affecting flowering the following year. After the flowers fade, the flower stalks should be cut off.
3. In winter, attention should be paid to cold protection. Terrestrial orchids have strong cold resistance, while tropical orchids require a higher overwintering temperature, so they should be moved indoors early or protected from the cold with plastic sheds to avoid freezing damage. The room temperature is best kept at 10 to 15°C, and ventilation should be noted during indoor care. As the climate gradually warms in early spring, the orchids can gradually be moved to the courtyard or balcony.
4. For home cultivation of orchids, natural rainwater, stream water, well water, and river water are best. If tap water is used, it should first be stored in a vat, exposed to the sun to remove bleaching powder, and then used. If tap water is used to water flowers for a long time, the growing medium will gradually become alkaline. Ferrous sulfate can be applied once every so often to increase soil acidity. In addition, watering orchids with fermented rice-washing water can also keep the soil in a slightly acidic state.
VIII. Propagation methods
Orchids are mostly propagated by division and tissue culture, while seed sowing is used for breeding varieties.
1. Division propagation: Division is carried out in spring and autumn, varying according to the species. Species that bloom in winter and spring should be divided in late autumn; species that bloom in summer and autumn should be divided in early spring before sprouting. Generally, divide once every 2 to 3 years. Before division, watering should be reduced so that the potting soil is appropriately dry; when dividing, hold the pot with your hands, gently knock the mother plant out of the pot, remove the soil, cut off rotten roots and leaves, then wash clean with clear water and place in a shady spot to air-dry for 3 to 5 hours. After the surface water has disappeared and the roots turn white, become soft, and are slightly wrinkled, use a sharp knife to cut apart from the middle of the pseudobulb, apply plant ash to the cut to prevent rot, and plant immediately after drying in the shade. Be careful during division to avoid bruising the leaf buds and fleshy roots. After potting, place in a shady spot, and after growth resumes, return to normal management.
2. Tissue culture rapid propagation: In recent years, China has already used tissue culture technology for large-scale orchid production. In addition to propagating orchids, tissue culture technology is also widely used in propagating tropical orchids such as Phalaenopsis, Cymbidium hybridum, and Dendrobium.