Oncidium Orchid
The Oncidium Orchid refers to any orchid in the Oncidium genus. Because there are 330 species in this orchid family, there is talk of dividing it into multiple families. The very first Oncidium orchid was discovered by Olof Swartz in 1800. Most of the orchids in this family are epiphytes but some are terrestrials. The Oncidium Orchid grows in Northern Mexico, South Florida, South America, and the Caribbean.
All of the orchids in the Oncidium family have certain similar characteristics: column wings, a complicated callus on the lip, and pseudobulbs that vary from one to three leaves. The flowers in this family come in varying shades of pinks, reds, whites and yellows. Because of the callus, the lip looks enormous and is ruffled.
Traditionally the Oncidium Orchid has fallen into one of three categories though these are being re-categorized. The first group has pseudobulbs that are green with long racemes and small flowers. Most of the flowers in this group are yellow, yellowish-brown or brownish.
A second group of Oncidiums has very stiff leaves and smaller pseudobulbs. These have yellow flowers but a tremendous variety of sizes. Some of these orchids are only a couple of centimeters long while others have racemes more than one meter long with 30 cm leaves. These orchids were known as Mule-Ears but now are classified as Psychopsis.
A third group of Oncidium orchids is now classified as Tolumnia. These used to be named Varigata or equitant oncidiums. This group has no pseudobulbs. Their leaves act as storage for the nutrients the plant needs to survive. The plants and flowers are very small but come in a large variety of superb colors. Other Oncidium orchids are now known as a new family named Cyrtochilum. These have a pseudobulb and inflorescences that can reach twenty feet long.
Because of the wide range of locations and sizes of Oncidium orchids, their care needs differ greatly. Generally speaking, they need either bright light or several hours of sun each day. Some shade is required. These orchids also grow well under artificial light. Temperatures should reach 80 to 85 degrees during the day and can drop to 55-60 degrees at night. Some of these plants can tolerate heat from 95 to 100 degrees if it is humid and there is some air movement. Plants should be watered every 1-2 days in the summer and they can go up to ten days in the winter. Normally humidity should be kept between 30 and 60 percent.
If you want to try growing any of these Oncidiums at home, it is advisable to keep the pots on a tray covered with rocks with water below. Fertilizing is necessary--a 30-10-10 formula if you plant in bark, and 20-20-20 in other planting mediums.