| kmarch is correct and here are a few more facts.
They are deciduous so that no water during dormancy but heavy water and fertilizer once new growth starts. They will look dead all winter. They usually loose all leaves before flowering but not always.
The do not grow into large bunches of pseudobulbs like other orchids and need to be divided regularly. I will have to check on the specifics but some will normally not support more than two growing bulbs and the extras die off (and look like rot).
Normally only one bulb will flower on a plant.
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jerry  |