Phaius Culture

Question

Please tell me how to grow Phaius (nun's cap). I noticed that a plant bought is planted in more of a soil mixture rather than bark, Is this the kind of medium that it needs? Please also tell me about light, blooming frequency, and what the flower will look like. —Susan Littlefield

Phaius tankervilleae flowering at the AOS Botanical Garden. photo © 2004 Greg Allikas

Answer

Phaius tankervilleae, commonly known as the nun orchid or nun's cap, is becoming increasingly available as a potted plant at garden centers. It is a large-growing terrestrial that is appropriately planted in a medium such as one you might prepare for cymbidiums, spathoglottis or other terrestrial orchids. A possible mix could consist of three parts fine fir bark, one part peat and one part sponge rock (not perlite, which is too fine-grained). Its inflorescences appear in early winter and flowers emerge in January into February. This plant grows well under Cattleya-like conditions: bright light and slight drying between waterings. Phaius will tolerate temperatures down into the lower 40s, but will not grow well if exposed to such low temperatures for any length of time. Tropical days, up to 80 or 90 F, with tropical humidity, are beneficial. In frost-free areas, this orchid can also be grown outdoors. It is grown as a garden plant in South Florida and may have been the first tropical orchid grown in that state. —Ned Nash