North of England Orchid Society - An introduction to oncidium orchid culture...

North of England Orchid Society -

An introduction to oncidium orchid culture...


Are a very large genus  which grow naturally throughout the tropical zones of the American Continent and Caribbean.
Often referred to as Dancing Lady Orchids, because of the similarity to some of their flowers to a Latin American dancer.

Identification of variety.

Look for pseudobulbs which are green and have long racemes these have small golden yellow flowers sometimes with red/brown horizontal striping or brwny yellow. They may have very dominany deep red colouration and others have white or pink blooms.
Others can have very small pseudobulbs with very stiff erect leaves. The leaves are a water reserve for the plant. The racemes aare long bearing yellow flowers which spread out from the top of the plant originally referred to as mule eared orchids, they are more recently classified as Psychopsis orchids.
Then  there are the equitant oncidiums which have no pseudoblubs but triangular to oval broad fleshy leaves which again operate as a water reservoir. The flowers have the mostexquisite coloration, more recently they have been re classified at Tolumnia.

Finally there is another tyoe which has long winding flower stem reaching over 20feet these are classified as Cyrtochilum.

How to Grow oncidium Orchids

Cultural information

oncidium Orchids....

These orchids can be varied in their cultural requirements, the hybrids are tolerant of wide ranges in temperature, and broadly speaking do best in an intermediate environment. There are many varieties however spread throughout the world, and cultural requirements differ widely amongst the species, hence the following is given as a general rule for most hybrids.

Temperature and Humidity
Minimum night temperatures of 10 -15 C, depending on the plants' origin, are needed, but growth in summer is rapid at temperatures up to 26 C. A humid atmosphere, propelled by a fan is beneficial. Light In greenhouses, the normal maximum is 40/50% of full daylight or 1000-2500 foot candles. In hot weather shade sufficiently to ensure that the leaves are cool to the touch. If you are growing in the home give a bright situation but not direct sunlight, behind a net curtain, from April to September. These also make good conservatory plants as long as summer shade and good air movement can be provided.

Watering and Fertilising
From March to September the compost should never be allowed to dry out completely. Water twice weekly and fertilise fortnightly with a recommended orchid fertiliser. From October to February, no fertiliser is needed, but water the plants when the compost appears dried out. It is better to underwater as the plants can stand neglect more than over watering! Compost and potting A medium bark mix will do well with added polystyrene spheres or perlite to keep it open. Chopped sphagnum helps retain humidity and some charcoal keeps it 'sweet'. New compost will keep the plant growing for two to three years before it turns acid and the plant needs repotting.  

The best time to repot is when the new roots are just beginning to appear at the new shoot's base.

Categories orchid culture, oncidium orchids, orchid society, north of england.