Masdevallia Orchid Factsheet
These Pleurothallids have a reputation for being difficult to grow, but nothing could be farther from the truth. They are fussy if the temperatures are too warm, though, hence the bad reputation. Give them cool temperatures and they are quite easy to grow. A dark shady greenhouse in the heat of summer and a bubbled wrapped greenhouse in winter keeping temp above 7c with a heat tube will be fine.
Culture of Masdevallia Orchids
They need cool growing temperatures. Keep the daytime temperatures below 25C. At night, temperatures should drop at least 8C. They care a great deal about leaf temperatures, so respect this. The plants also dehydrate quickly if temperatures are too high, as they cannot close their stomata to retain moisture. Oncidium can cope with less water due to the psuedobulbs.
Shaded light only. Tend to be happy at 600 - 1500 ft candles of light (very winter Temp is 7C.shady). The higher the lighting, the cooler the temperatures need to be.
A very light feeding of a well balanced fertilizer will keep them blooming. Too much fertilizer will cause the tips of leaves to turn brown or black. Bloom feed August to April.
Require high quality water. Rain water is ideal. Do not over water, keep lightly moist
Humidity & Air
Humidity is very important for all Pluerothallidinae, as they come from cloud forests in the Andes. Try for 70 to 80% humidity. Good air circulation (from a fan) will help prevent issues with rot. The grower may want to invest in a humidifier to keep humidity up, but only necessary on hot days, misting down, or damping of the floor can suffice. Oncidium like good air circulation and can tolerate lower humidity.