In most circumstances, a wrinkled pseudobulb will indicate a lack or water or humidity. That may occur because not enough water and humidity have been offered to the plant, or the roots have been damaged and no longer absorb water as they should. Some orchids, notably Oncidium alliance plants, can have a naturally grooved pseudobulb that may become more pleated as it matures. And in some orchids, notably Cattleya, older pseudobulbs lose their leaves and become shriveled simply as a matter of age, though they still provide an important function to the plant and nourish its other parts.

If a mature orchid has had an ungrooved pseudobulb in the past and it is becoming wrinkled, check its water and humidity as well as the conditions at the roots. 

For more information on growing orchids, see our Caring for your Orchid guide.

Courtesy of NYBG Plant Information Service