Oncidium Orchids are cousins of the Lady Slipper and Moth orchids. These Orchids need abundant amounts of light to produce large flowers. This is one of the few Orchids that typically enjoys a few hours a day of direct sunlight. You should notice light green leave and dark green is a sign of an inadequate amount of light.
The roots of a Onicidium Orchid are prone to root rot and need a period of dryness between each watering. This makes them a hard Orchid to care for by beginners because of the needy schedule. Place you Orchid in a west facing window, preferably behind a shaded curtain to lessen some of the direct sunlight but still provide enough.
Water this Orchid fully when the growing medium is completely dry. This orchid likes to dry out and get air to the roots between watering, so don’t water until its completely dry. The easiest way to tell is by learning the weight or your tree when moist and dry. This will allow you to test for moisture extremely quick and accurately.
During the growing season, feed your Onicidium Orchid with a high nitrogen fertilizer. Use a well balance fertilizer for the rest of the year. This Orchid does not do well with too much fertilizer so feed every other week at half strength. It is also a good idea to flush left over fertilizer in this Orchid once a week.