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Major Groups, Families and Genera

Orchidaceae

Frequently Asked Questions (FAQs)

What is an orchid?
What should I do if I find an orchid in the wild?
Are there any orchids that are native to Britain & Ireland?
Which is the largest orchid?
Which is the smallest orchid?
Which is the largest genus of orchids?
How can I get my orchid house-plant to re-flower?
Why is my orchid house-plant dying?

Eulophia zeyheri Hook.f.

Q. What is an orchid?
A. All orchids have protocorms, and these are not found in any other family. A protocorm is the structure formed after the germination of the seed and before the development of the seedling plant. The protocorm has no radicle and instead has mycotrophic tissue (and hence differs from other flowering plant seedlings).

Other important characters shared by most orchids include:
* The fusion of the male and female organs into a single structure, called the column.
* They have large numbers of small seeds per ovary.
* Stamens are found on the abaxial side of the flower (the side facing downwards/away from the stem).
* The lip/labellum (a modified petal) occurs opposite the fertile stamen(s).
* Flowers are often resupinate (have twisted through 180° during development).
* Pollen is usually bound together to form large masses (called pollinia).
More details on 'What is an orchid?'

Q. What should I do if I find an orchid in the wild?
A. You should leave it alone (NEVER pick wild orchids). If you think it may be rare then get in contact with your local wildlife trust (see www.wildlifetrusts.org for the UK).

Q. Are there any orchids that are native to Britain & Ireland?
A. Yes, there are 46 species of orchids that are thought to be fully resident in Britain & Ireland. These include the rare lady’s slipper orchid and lizard orchid, as well as more common species such as the bee orchid, which can be found in most counties of England and Wales.

Q. Which is the largest orchid?
A. The largest orchids are probably vanillas, which are lianas that reach into the crowns of rain-forests trees and may be 20 metres or more in length. Some tropical orchids also form very large clumps on rocks or in trees. Grammatophyllum speciosum plants of several hundred kilograms have been reported from Southeast Asia.

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Q. Which is the smallest orchid?
A. The smallest orchid is thought to be Bulbophyllum minutissimum which is 3-4 mm tall, but many other orchids approach it in size.

Q. Which is the largest genus of orchids?
A. Bulbophyllum is probably the largest orchid genus. It currently includes about 1800 accepted species.

Q. How can I get my orchid house-plant to re-flower?
A. This will depend on the type of orchid that you are growing, but it is worth bearing in mind that many orchids need a 5-10°C drop in temperature at night to initiate flowering.
For further information on growing orchids see the Royal Horticultural Society’s Help & Advice Pages:
Growing orchids - Cymbidium and Phalaenopsis
Growing orchids - Odontoglossum and Paphiopedilum

Q. Why is my orchid house-plant dying?
A. There could be many reasons for this, but one of the most common problems is over-watering.
For further information on growing orchids see the Royal Horticultural Society’s Help & Advice Pages:
Growing orchids - Cymbidium and Phalaenopsis
Growing orchids - Odontoglossum and Paphiopedilum

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