James Keith
Family
Orchidaceae
Botanical Name
Oncidium
Plant Common Name
Dancing Ladies Orchid, Orchid
General Description
Oncidium is a large and diverse group of orchids. They are New World plants native to the tropical Americas. There are about 350 species whose origins range from hot moist coastal areas to cool dry habitats high in the Andes of Peru. They have lovely flowers held on long stems. The delicate blooms flutter in the wind, which may be why these orchids are sometimes called “dancing ladies.”
Most Oncidum are epiphytes (tree dwellers), while others are lithophytes (rock dwellers). A few are terrestrial, meaning they grow in soil like most other plants. The habits and flowers are extremely variable but share common characteristics that mark them as orchids. They are monocots, which means they are related to plants like lilies and grasses, and their foliage is often linear with parallel leaf veins and flower parts in threes.
Oncidium may be very small or large. Most exhibit sympodial growth. Sympodial orchids have bulbous water-storing bases called pseudobulbs and creep laterally along growing surfaces with thick roots that appear at the base of the bulbs. The pseudobulbs of Oncidium may be large, very reduced or absent. The leaves are few, one to three per psuedobulb, and are separate or fan-like in arrangement. The roots of epiphytic species are often covered with a protective spongy surface called velamen, which aids in water and nutrient absorption.
The flowers are usually produced in large numbers on long airy sprays, though a few species produce blooms singly. They usually have two rows of three showy petal/tepals. One or more of the petals is usually large, lip-like and designed to attract insects, mostly bees, to the flowers for pollination. In the flower, male and female reproductive parts are fused into a single winged structure called the column. It holds the pollen that is usually bound together into two large masses, called pollinia, which only orchids have. The flowers are most commonly in shades of yellow and brown, but red and white blooms are also available. The dust-like seeds are produced by the thousands to millions in bulbous pods.
Oncidium culture is as variable the natural areas they inhabit. Each species has its own needs for best growth and flowering. Many are sub-tropical or tropical epiphytes and prefer bright filtered light, high humidity and regular water. Epiphytes grow best in special mixes of bark and fern while terrestrials need rich potting soil. Orchids are thought to be difficult to grow, but many are quite easy if given the right growing environments. Most will thrive in a bright window (no full sun) on a tray of rocks, to increase drainage and humidity, and prefer regular water and orchid fertilizer. In other words, care for them as you would any house plant. No magic is required.
