Detailed Guide to Orchid Division Propagation Techniques and Pest and Disease Control Methods

There are about 500 genera and more than 10,000 species of orchids in China. The orchids commonly appreciated are terrestrial orchid varieties of the genus Cymbidium. According to their flowering periods, they can be roughly divided into spring orchids, summer orchids, autumn orchids, cold orchids and ink orchids. There are many varieties of orchids, including plain-heart, lotus-petal, plum-petal, narcissus-petal and butterfly-petal types. Many people think that growing orchids is quite mysterious and difficult to do well, but in fact, as long as you grasp their growth habits, you can grow them well. Orchids like cleanliness. They cannot tolerate dust and grime, and grow especially vigorously in warm, humid, semi-shaded places facing south with relatively more sunlight.

Orchids are propagated by seeding and division.

Orchid seeds can be sown as soon as they are collected. Orchids have a special characteristic: the orchid roots must live symbiotically with orchid fungi in order to survive. Therefore, when sowing, the seeds are often sown on the surface of the mother plant's pot, using the mother plant's orchid fungi to germinate and grow. The seeds germinate after about half a year, and after growing in the mother pot for two months, they can be moved to small pots for cultivation.

The division method is the method commonly used at present. Because orchid species differ and their characteristics vary, when is the best time to divide them is a matter on which famous orchid growers each have their own views. Generally speaking, the more suitable times are spring, before new buds emerge, and autumn, when orchids gradually stop growing. At these times, new buds are not easily bruised or broken, the temperature is relatively mild, and it is convenient for handling and for restoring the plant body. Summer temperatures are high, which is the peak growing season for orchids, while winter is cold and the plant body has weaker resistance, so division is mostly unfavorable. You can also divide them after flowering has ended. Generally, those that bloom in summer and autumn should be divided in early spring; those that bloom in early spring should be divided in late autumn. In this way, flowering is not affected, and it can also stimulate the tillering of leaf buds, making the leaves green and the flowers bright.

When dividing, take the mother plant out of the pot, shake off the soil, and cut it into several clumps with a knife. Each clump should carry 3-4 pseudobulbs and new buds, and dead and withered leaves and rotten, shrunken roots should be trimmed away. If using wild orchids bought from the market, because the root system has mostly lost water and shriveled, they can first be soaked in clean water. After they have absorbed enough water, wash and clean the roots, then dry them in the shade until the roots turn white before planting.

For planting orchids, black mountain soil, peat soil, garden soil, pine needle soil, moss, fern roots, bark chunks, etc. can be used. Cover the drainage hole at the bottom of the pot with a piece of tile, then spread a layer of broken brick and stone granules with a thickness of one quarter of the pot depth to enhance air permeability and drainage, and then spread a layer of cultivation soil. Hold the orchid upright and plant it, fill in the cultivation soil, and cover the pseudobulbs. The soil should be pressed firm, and no soil should be filled within 2 cm of the pot rim, to make watering easier. After planting, water thoroughly, and place it in a cool, shaded place. After half a month, move it to a sunny, ventilated environment for cultivation. To increase beauty and moisture retention, a layer of small crushed white stones can be spread on the pot surface.

There are four prohibitions in growing orchids: do not take them out in spring, do not expose them to the sun in summer, do not let them dry out in autumn, and do not keep them wet in winter. In spring, the temperature is still unstable, and taking them out of the room too early makes them vulnerable to wind and cold. It is relatively safe to take them out in early April. In summer, they should be placed under a shade frame, avoiding direct sunlight, and cultivated with scattered light. Autumn is the period when orchids sprout and send up flower spikes, so corresponding humidity should be maintained and dryness avoided. Orchid roots are fleshy, and in winter dormancy the water requirement is not great, so the pot soil only needs to be slightly moist; do not water too much, so as to avoid diseases of the roots and leaves.

Fertilizer should be dilute, not concentrated: during the growing period, apply once every half month with decomposed bean cake water or horse hoof sauce residue water. If an appropriate amount of potassium dihydrogen phosphate is added, the effect is even better. Do not fertilize in the heat of summer. When the temperature is too high (above 32°C), in addition to daily watering, spray water several times more. Slightly acidic water is suitable. Frequently spray and wash the leaf surfaces with clean water; this not only improves the growing environment of the potted orchids, but also keeps the leaves clean and reduces the chance of pest and disease infection.

Orchids are prone to scale insects, which can be sprayed with a 1000-fold dilution of dichlorvos emulsifiable concentrate. When whiteflies cause damage, spray and kill them with a 2000-fold dilution of deltamethrin. Orchid roots have a sweet taste and easily attract ants, which can be lured and eliminated with meat bones. Orchids are prone to anthracnose fungi and black spot fungi. After disease occurs, promptly remove diseased leaves and burn them, and increase the spacing between potted plants to improve ventilation and light conditions. Reduce water spraying, control humidity, and combine this with carbendazim for prevention and control.