Dormancy

Question

This year all my Catasetum Alliance and calanthes went from leaf drop to new growth without going dormant. Could this have anything to do with this year's weather here in the Bay area? —Patrick T. Duffy

In nature dormancy in deciduous orchids  such as Catsetum saccatum is triggered  by a distinct dry season — photo © 2009 Greg Allikas

Answer

Yes, indeed, it could have been unusual weather patterns. Especially if cool and foggy conditions prevented proper maturation of growth until very late in the season, the plants may simply begin growing again. The solution to this for plants that require a dormant period to initiate flowering is to begin to withhold water and fertilizer in late autumn, whether or not you feel the growth has reached full growth. This will slow down the plant and initiate dormancy. This is also important with many dendrobiums from monsoonal climates. —Ned Nash