Cycnoches Orchids
Cycnoches orchids are relatives of Catasetum that often have very dramatic flowers. The growth habit is a bit unusual; they are sympodial orchids with very large, thick pseudobulbs covered in a layer of papery, light-brown bracts, and with a spray of large, veined leaves mostly near the top of the pseudobulb. After flowering, they drop their leaves and require a dry rest until they begin growing again and new roots are an inch or two long; watering during the dry season, except the bare minimum required to keep the pseudobulbs from shriveling, will cause the plant to rot and die. Many orchidists repot these orchids during the dry rest, often dividing the plant so that there is one pseudobulb per pot. These plants have unisexual flowers, meaning male and female flowers occur on separate plants (or, rarely, in different flowers on the same inflorescence.) Which sex of flowers is produced seems to be partly controlled by temperature and light intensity, but it's hard to predict. The two types of flowers often look quite different from each other.
Cyc. herrenhusanum
Image courtesy of orchidgalore
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