Orchid Growth Types:

Sympodial, Monopolidal

There are two main growth types in orchids sympodial (multiple stem) and the monopodial (single stem). In order to grow orchids successfully, its important to understand each type of growth so that you can treat them correctly. Sympodial growth is more common among orchids. Most of these orchids have pseudobulbs which function as storage reservoirs for food and water. The plant will hold pseudobulbs vertically and send out new growth horizontally between the pseudobulbs. They function very much like rhizomes on terrestrial plants, although they are part of the plant rather than a root. The growth begins at the base of the pseudobulb and is called a lead. Both the shoot and roots will grow from this lead. Many times more than one growth at a time will be present. Leaves can last for several years and provide nourishment to the plant until they turn brown and die. Even without a leaf, the pseudobulb will continue to support the plant and provide nourishment for growth and flowering. Examples of sympodial orchids are Cattleya, Paphiopedilum, Oncidium, and Dendrobium. These orchids will grow from one side of a pot to the other and will eventually grow right out of the container. They need to be repotted every two or three years and can easily be divided to produce new plants. Some large Cattleyas can grow out of their pots even faster! The second growth type is monopodial. In this type of growth there is one main stem which grows indefinitely from the center of the plant. Normally, the stem grows straight up and aerial roots sprout from where the stem and leaves meet. The plant will lose its leaves from the ground up, continually growing new leaves from the tip and making new roots along the stem. Examples of monopodial orchids are Phalaenopsis and Vanda. The foliage is generally thick and leathery and grows alternately on the stem. Inflorescences rise from the stem at the base in the case of Phalaenopsis or from between leaves in the case of Vanda. These plants can be kept in one pot until the medium breaks down. Then the plant is simply removed from the old potting material, cleaned up and put in a new pot. One problem that does arise at some point is that there is a bare stem at the bottom. The plant can be divided as long as there are roots on the top piece. The remaining piece will sometimes produce keikis (baby plants) from the sides of the original plant.