Introducing...
Oncidium orchids (cool growing)
Botanical name: Oncidium
Common name: Cambria type orchid, tiger orchid
These orchids produce eye-catching displays of exotic flowers on tall stems. The Cambria types are the best choice to grow as houseplants in a cool, bright room – many of the others can be trickier to look after, needing specific temperatures and high humidity, so are often more suitable for a cool greenhouse.
Looks
Cool growing oncidiums produce exotic flowers of various colours, including white, pink and reddish-purple, often with darker spots or blotches. The small flowers are held on tall stems above clumps of long, narrow leaves that sprout from large swollen ‘pseudobulbs’ at the base.
Likes
These oncidiums grow best in bright but filtered light, such as near a north- or north-east facing window. They need high humidity and cool temperatures of 16–21°C (60–70°F), with a drop of up to 10°C (20°F) at night. Grow them in pots of bark-based orchid compost.
Dislikes
As their name implies, cool growing oncidiums don’t like to be too warm (ideally not above 21°C/70°F in summer), but also not too cold, so at least 11°C (20°F) in winter. They dislike low light and dry air. Overwatering and damp compost can cause rotting, so let them dry out between waterings, especially in winter.
Did you know?
This group of orchids used to be known botanically as Odontoglossum (tiger orchids), but have been reclassified as Oncidium. However, they like cooler growing conditions than traditional oncidiums, hence the name ‘cool growing’ oncidiums (while traditional oncidiums are now ‘warm growing’) – this helps to distinguish between the two groups, so you can provide the right growing conditions.
Growing guide
How to grow ‘cool growing’ oncidium orchids
All the information you’ll need to grow these stunning orchids in your home or greenhouse.
Useful advice
Christmas-flowering houseplants
How to grow houseplants
How to grow oncidium orchids (warm growing)
Humidity for houseplants
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