Orchids may be propagated either sexually or asexually. Since, most orchids do not come true from seed, once a hybrid or clonal selection has been made, then all further propagation is done asexual means to be some off-spring will be true to type.
Seed germination technique
Orchid seeds are very small, usually 80-130 μm wide and 470-560 μm long. If put end to end it would take 50 seeds to make a line of 2.5 cm long. The seeds are not only small but also lack of endosperm and hence are difficult to germinate. In their native habitats, germination takes place only when certain fungi are present which supply sugars to germinating seeds until such time as the seedling has sufficient chlorophyll to produce its own sugar and sustain itself.
Vegetative propagation
Tip Cuttings of orchids:
Most monopodial orchids (Vanda, Arachnis) can be propagated by tip cuttings. Vanda tip cuttings are usually 30-37 cm tall and bear up to 12 leaves and usually few aerial roots. Cuttings can be potted and will grow without being put in a propagation bed. Arachins cuttings are usually 45-60 cm in length. They, too will have aerial roots and can be potted directly.
Some monopodial and sympodial orchids produce off-sets. Those genera such as Dendrobium and Epidendrum produce off-sets in leaf axil. The 3-4 root off-sets can be snapped off and potted up.
Division of parent clump in orchids:
Cattelya and other sympodial orchids are propagated by division of the parent clump. This is usually accomplished on plants that have six or more pseudo-bulbs. The rhizome is cut between the third and forth pseudo-bulbs and both sections are potted up as individual plants. Since, most cattleya plants produce only one new leaf per year, most plants are divided every three years. Genera such as Paphiopedilum and Cymbidium can be divided more frequently, as a division containing only one fan of leaves or one pseudo-bulb is all that is necessary to increase these plants.
Crops Calendar