Culture Notes – Oncidium Alliance

This diverse group originate in South America. Some species are tropical, but most prefer sub-tropical or temperate climates. The almoscendless variety of colours & flower shape have made this group popular.

Temperature & Light
Some of the spidery style flowers (Brassia’s) are sensitive to cold, so a 5° or 6° celcius minimum is recommended. Medium to heavy shade is preferred.
Watering & Fertilising
Water regularly whilst growth is active, then water sparingly after growth has matured. Include a soluable fertiliser, recommended for flowering plants, with every second or third watering all year round. As a general practice, try not to wet the leaves during hot, sunny weather. Favour Watering during the evening in Summer Keep them as dry as possible during very cold weather.
Potting
These epiphytic orchids need good drainage. A blended medium which is well draining is ideal and plants prefer to be cramped in the pot. Some of the dancing lady style also do well on mounts of tree fern fibre or even cork.
Pests & Disease
Most oncidiums have soft leaves that are prone to black spot & some leaf spot diseases. Regular (every month or so) application of Mancozeb during Summer will help prevent this. Mealy bug can sometimes attack leaves and roots but is easily controlled with Rogor or similar These plants are relatively pest free.

Most of the modern hybrids will flower regularly during the year. Look for Odontoglossums, Miltassias’s, Beallara’s and many others in the Oncidium group.

Countesy of Tinonee Orchid Nursery.