How to grow potted orchids well? The latest care methods
Orchids are also known as spring orchid, orchid grass, secluded orchid, national fragrance, etc. They are epiphytic or terrestrial herbaceous plants of the genus Cymbidium in the family Orchidaceae. Orchid cultivation in China has a history of about two thousand years. Chinese people have always regarded orchids as a symbol of purity and elegance, and together with “plum, bamboo, and chrysanthemum” they are called the “Four Gentlemen.” They have extremely high ornamental and cultivation value. Now let us take a look at how to grow potted orchids well!
Orchid growth habits
Orchids originally grow in hilly areas or beside mountain springs and flowing water in continuous ranges of lofty mountains and steep ridges. Some grow in deep valleys and ravines on sloping hillsides with dense trees, or in crevices with rocks and relatively deep soil layers. Because orchid types differ, their living habits also vary. Spring orchids prefer shade, while summer orchids prefer sun, but both prefer warm and humid climates. Orchid roots are distributed on the surface layer of the soil and require soil rich in humus, loose in texture, with good water permeability, fertilizer retention, and water retention. The soil is acidic, with a pH value between 5.5 and 6.5. Orchids are most averse to coal smoke and dust, and they also fear scorching sun and violent wind and rain. Places with air pollution are not conducive to orchid growth. The root system needs orchid mycorrhizal fungi to live symbiotically with it, otherwise growth is poor.
Orchid propagation methods
1. Division: This can be done in both spring and autumn, generally once every three years. Any plant with robust growth and crowded pseudobulbs can be divided. After division, each clump must retain at least 5 pseudobulbs connected together. Before division, reduce watering to make the potting soil relatively dry. When potting after division, first cover the drainage hole at the bottom of the pot with broken tiles, then spread coarse gravel to occupy 1/5 to 1/4 of the pot depth, then place coarse-grained soil and a small amount of fine soil, and then plant with sandy loam rich in humus.
2. Sowing: Orchid seeds are extremely fine. Inside the seed there is only one incompletely developed embryo, and the germination capacity is very low. In addition, the seed coat does not easily absorb water, so sowing by conventional methods cannot cause germination. Therefore, orchid mycorrhizal fungi or an artificial culture medium is needed to supply nutrients before germination can occur.
How to grow potted orchids?
1. Soil: Orchid soil should be mainly humus, primarily using 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 other materials can also be artificially mixed into a loose, air-permeable, 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 mixed evenly.
2. Fertilizing: Orchid topdressing mostly uses liquid fertilizer or foliar fertilizer, and the concentration should be lighter than for other flowers. Generally, during the growing season, a fully rotted dilute cake fertilizer water of about 15%, or 0.1% urea fertilizer water plus 0.2% potassium dihydrogen phosphate fertilizer water, can be applied once every 15 to 20 days. From before flowering to the flowering period, 0.2% potassium dihydrogen 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 unrotted fertilizer must not be applied, to avoid root rot.
3. Watering: Watering orchids depends on the species, growth condition, and local climate. It should be kept moist but not wet, dry but not parched. Watering should not be too much or too little. Grasp the principle of not dry in autumn and not wet in winter. In winter, when the temperature is low, the plant is in a dormant state, so watering should be controlled, generally once every 5 to 7 days. However, Cymbidium sinense, which blooms in winter, needs more water. In spring and autumn, water once every 2 to 3 days. In summer, water 1 to 2 times a day on average.
4. Temperature: In the north, potted orchids should be moved indoors around the Frost's Descent solar term when the temperature drops to 5°C. In the early period after being moved indoors, windows should be opened frequently to maintain air circulation. In winter, the indoor temperature should preferably remain around 10°C. After Grain Rain, move them outdoors for care. The suitable growth temperature for orchids 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. Temperature and humidity must not be too high. In summer, the temperature should not exceed 30°C.
5. Light: Orchids prefer shade and fear direct strong light, so shading should be provided 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 curtain shading. Generally, shade from 9 a.m. to before 6 p.m., and pull the curtain open in the early morning and after 6 p.m. so they receive scattered sunlight. In winter, move them indoors to a place with visible scattered light, but also avoid direct sunlight. Among orchids, Cymbidium sinense has the strongest shade tolerance, followed by Cymbidium ensifolium, while spring orchid and Cymbidium faberi have weaker shade tolerance.
6. Pruning: During orchid cultivation, the plant should be pruned. For example, when old leaves turn yellow and withered, they all need to be pruned, which benefits the growth of other leaves and also improves ventilation. Diseased leaves especially need timely pruning to prevent contagion. In addition, scissors also need to be disinfected to prevent infection.
7. Repotting: Orchids grow relatively slowly, so 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 the soil is filled to halfway, lift the orchid seedling gently while shaking the flower pot so that the soil and roots combine closely. When the soil is filled to 2 to 3 cm from the pot rim, press gently with the hand.
Precautions for orchids
1. Orchids are mainly distributed in the southeast and southwest regions. They mostly grow wild under sparse forests in humid valleys and in shaded places by rocks, so they prefer warm and humid climates, prefer shade and moisture, and require a shading degree of 70 to 90%. They avoid high temperature, dryness, and strong light.
2. During orchid cultivation, withered yellow old leaves and diseased or insect-damaged leaves should be continuously cut off to facilitate ventilation. After flower buds emerge, 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 scapes should be cut off.
3. Orchids should be protected from cold in winter. Terrestrial orchids have strong cold resistance, while tropical orchids require a relatively high overwintering temperature. They should be moved indoors early or protected from cold with a plastic shed to avoid freezing. The room temperature should preferably remain at 10 to 15°C. Attention should be paid to ventilation during indoor care. As the climate gradually warms in early spring, gradually move the orchids to the courtyard or balcony.
4. For home orchid cultivation, natural rainwater, stream water, well water, and river water are best for watering. If tap water is used, it should first be stored in a vat and exposed to the sun to remove bleaching powder before use. If tap water is used to water flowers for a long time, the growing medium will gradually become alkaline.
5. When cultivating orchids, ferrous sulfate can be applied once at intervals to increase soil acidity. In addition, watering orchids with fermented rice-washing water can also keep the soil in a slightly acidic state.