What are the propagation methods for orchids? Beginners can master them easily too

Shen Yuanru, "Orchids," Part Twelve: Orchid Propagation Methods (1)

Orchid propagation falls into two types: asexual and sexual. Propagation using part of the vegetative body is called asexual propagation; propagation using seeds is called sexual propagation. In China, the division method within asexual propagation has traditionally been most commonly used, while sexual propagation, because it requires rich experience, skilled technique, and certain equipment conditions in the processes of pollination, seed collection, sowing, and seedling raising, is generally used only by research institutions when breeding new varieties.

(1) Asexual propagation

1. Division method. The orchid is a plant with pseudobulbs. When the pseudobulbs have multiplied to a certain point, they can be cut apart between one another with a sharp thin-bladed knife or scissors, and then planted separately in pots to become new plants; this method is called the division method, and according to the custom of China's orchid-growing circles, it is commonly known as "dividing the pot" or "dividing the clump." This method seems simple, but due to the plant's physiological habits, seasonal restrictions, and technical handling, it is still rather complex and not easy to do at once. Now, based on China's traditional rules and the author's many years of practical experience, it is described as follows:

(1) Suitable time for division. Division propagation can generally be carried out except during the severe cold and the height of summer, but the most suitable period is around April or September (that is, during the period from "Qingming" to "Guyu," when the climate gradually warms in spring, the daughter buds have not yet begun to sprout, and new roots have not yet grown; and around "Qiufen," when the daughter buds and flower buds have long since broken through the soil, sprouted into new growth, the young buds have emerged, most new roots have already formed, the temperature gradually turns cool in autumn, and the temperature difference is small. During these two periods, the plants easily recover their growth, and division has little effect on the orchids).

(2) Conditions and procedure for division. If potted orchids are well cultivated, division propagation can be carried out every three to five years, but Cymbidium goeringii must have four or five growths (each leaf cluster is called one growth), and Cymbidium faberi must have seven or eight growths; other types of orchids follow the same rule. Of course, the most ideal situation is to wait until there are too many leaf clusters in the pot, when, as the pseudobulbs continuously multiply and separate, a naturally wide gap band appears between the growths; this shape is commonly called a "road" in orchid-growing circles. After a "road" has formed, the pseudobulbs separate naturally from one another, and the root systems are also easy to detach, so that no wounds are caused, which helps each plant quickly recover its growth. Before division, watering must be reduced to let the soil in the pot become somewhat dry, because if the soil is too moist, the wet mud will stick to the roots when the pot is turned out, and the orchid roots are likely to break and be injured when the clump is split apart.

When dividing, first insert the index and middle fingers of the left hand into different positions between the leaf clusters, rest the thumb on the rim of the pot, and use the other two fingers to support the other side of the pot surface, then turn it upside down and hold it; with the heel of the right palm, gently tap all around the pot surface in succession. When the mud clump feels loose from the pot, grasp the round hole at the bottom of the pot with the right hand and slowly lift the pot out, so that the mud clump and the pot separate from each other. Next, lay the mud clump on its side or set it flat on the ground (if the root system is not much coiled, watch out that the mud clump does not suddenly crumble and break the orchid roots). If the root system is tightly coiled and intertwined and the mud clump is hard to break apart, pat lightly along the outer edge with the palm of the hand to gradually loosen the mud clump, or use a blunt-ended bamboo strip to pick away the soil, then loosen and untangle the coiled root system, place it in clean water and wash it (if tap water is used, it must be stored for many days so that the disinfectant in the water fully decomposes before use, so as not to affect the orchid roots), then move it to a ventilated, light-transmitting, cool place and let the water on the root system dry off. When the orchid roots appear chalky white, choose an appropriate position and use a sharp blade or thin-edged scissors to insert vertically between the pseudobulbs and cut them apart. At this time, be careful not to injure the tiny young leaf buds at the base of the pseudobulbs (because at this time the white leaf buds are extremely tender and break off very easily at the slightest touch). After separation, if the wound is not large, it may be left to nature; if the wound appears water-soaked, it may be disinfected with potassium permanganate or a dilute nicotine sulfate solution, or coated with sulfur powder, to prevent bacterial infection and rot. When splitting a "road," simply hold the pseudobulbs on both sides and gently twist, and the connection will quickly separate on its own. At the same time, cut off the shriveled pseudobulbs and the small, aged roots flush with the base of the pseudobulbs; if a section of a root is dried and hollow, cut it off along the junction of the hollow and solid parts (do not cut into the end face of the solid root, so as to avoid making a wound). Overly long coiled roots may be cut between root nodes; if there are no nodes, cut at an appropriate length, but planting must wait until the wound is somewhat dry. Under normal circumstances, longer root systems should be carefully coiled into the pot along their natural tendency. The yellow-green aged pseudobulbs without leaves that have been divided off, as long as they still have a few short small roots, can still be kept for cultivation, and can continue to sprout new shoots from their base. Dark brown remnants of leaf scars often adhere to the pseudobulbs and should be torn off from top to bottom along their direction. According to China's orchid-growing custom, each pot of orchids must have at least two growths to grow normally; if there are too few, the plant cannot quickly recover robust growth. For Cymbidium faberi and the like, because their metabolism is stronger, more leaf clusters must be retained when dividing.

(3) Cultivation and management after division. Before potting the separated plants, choose a pot more generous than the spreading tendency of the root system. If using clay pots, pay attention to the size of the hole at the bottom; if it is too small, since orchid roots are aerial roots and love a ventilated, well-drained environment, the hole should be enlarged. If using a special orchid pot with a large bottom hole, first use two pieces of clam shell or broken tile, placed parallel and opposite each other, each covering half of the hole (a thin slit should be left in the middle), then use similar materials to build up layer by layer, forming a cone or truncated cone shape (it must not exceed one-half the height of the pot). In addition, some use plastic mesh to cover the bottom hole, with a layer of fine stone grains or broken tile or brick grains the size of broad beans scattered on top. Or use a fired ceramic bowl-shaped object with many small holes, placed upside down to cover the hole. Some also use fine bamboo filaments or thick lead wire woven into a conical net seat at the bottom of the pot, covered with several layers of palm fiber; however, this method is rarely adopted now because it does not last long and easily rots, and the cost is high. After the bottom of the pot is covered, first use fine soil sifted to the size of soybeans and scatter it on top of the covering, generally until it is just covered. Then add a layer of soil fine as mung beans (about 1-2 cm thick). Finally, pour in orchid soil or loose sandy soil (the thickness depends on the length and spreading tendency of the root system). While gradually adding soil, gently press and cultivate it with the hand into a cone or steamed-bun shape, then lay the root system down along its tendency and spread it out somewhat evenly. After it is seated, it is best to have the top of the pseudobulbs and the base of the leaf clusters just about 0.5 cm below the pot rim (if a steamed-bun-style pot surface is to be made, it may be slightly higher). Afterward, in the process of gradually adding soil, because orchid soil is relatively loose, the fingers must gently press the soil along both sides of the roots so as not to bury the roots, until the pseudobulbs are shallowly covered. Then press all around between the pseudobulbs, and press gently and firmly in all four places on the pot surface, but do not press too firmly. Finally, hold the side of the pot with one hand and gently pat the pot rim with the other to make the soil in the pot even and firm. If planting in the high pot-surface form (that is, the soil layer on the pot surface built into a half steamed-bun arc), the base of the leaf clusters should be about two cm above the pot surface, and soil should be gradually added to pile it into an arc; then spread the previously removed soil-bearing Selaginella uncinata over it (it must not be too dense). After it is laid, scatter a little sparse dry soil over the Selaginella uncinata and press it firm with the palm; if using soil-free Selaginella uncinata, the scattered covering soil layer should be thicker. The purpose of laying Selaginella uncinata is mainly that, because it has dense fine roots, it can hold the loose humus soil pot surface in shape during heavy rain or daily watering, so that it is not washed away and destroyed; in addition, it can maintain a certain humidity in the pot surface soil layer, avoid high temperatures scorching the pseudobulbs and root system, and at the same time give the pot surface a verdant look, playing a decorative role. After all operations are completed, spray the pot surface with a fine-hole watering can until thoroughly sprayed. After about several minutes, use a long narrow horn board or a flexible bamboo strip, etc. (about 15 cm long, about 4 cm wide and about 0.2 cm thick at the bottom, about 3 cm wide and 0.3 cm thick at the top, with the two sides and the shovel edge slightly thinner) to extend along the inner side of the pot rim into the soil layer, and press in an arc angle toward the center of the pot, so that the pot surface forms a half arc and a finger-wide water channel is left along the four edges of the pot surface; then spray water again, so that the semicircular soil mound above the pot surface is even. After planting, insert a label on the front side of the pot, recording the variety number or writing the name. The label used may be made of chemical film (because it does not easily rot and is durable), cut into various forms, such as a long narrow strip, T-shape, butterfly shape, etc.