Bletilla striata 'Alba' is a deciduous terrestrial orchid native to temperate areas of China and Japan. The tuberous rhizomes give way to up to 2 foot (60 cm) papery, thin leaves. Light green leaves are plicate (pleated) and are about 3 inches (7.5 cm) wide. It is one of the easiest terrestrial orchids to grow. The plants are hardy down to 20°F (-7°C) in the landscape and will withstand temperatures down to 10°F (-12°C) if mulched heavily. Whether grown in containers or in the landscape it is a showy addition to any orchid collection.
Blooming: In the greenhouse, our plants bloom from late spring to early summer. The 1-2 inch (2.5-5 cm) flowers are in racemes with 3-7 flowers.
Culture: Bletilla striata 'Alba' need light shade and a moist, rich, well-drained soil mix. In the greenhouse, we use a soil mix consisting of 2 parts peat moss to 1 part loam to 2 parts coarse sand. To this mix we add bone meal at a rate of 1 cup for each 0.01 cu yards of soil mix. During the growing season, the plants are well watered and allowed to dry slightly before watering again. We fertilize the plant in early spring with a 15-30-15 fertilizer on a weekly basis until after flowering. After flowering, the plants are fertilized with a balanced fertilizer monthly until late fall when water is restricted. The plants are moved to the cool rooms for the winter rest period, and the nighttime temperature is never allowed to fall below 48°F (9°C). During this period, the plants are watered very sparingly. Too much water during this period can cause the tuberous rhizomes to rot.
Propagation: Bletilla striata 'Alba' is propagated by division in early spring before new growth starts. One should not divide clumps too often because they bloom best when crowded.
Bletilla striata 'Alba' was featured as Plant of the Week January 12-18, 2007.
Guide to Past Plants-of-the-Week:
Cal's Plant of the Week was provided as a service by the University of Oklahoma Department of Microbiology & Plant Biology and specifically the late Cal Lemke, who used to be OU's botany greenhouse grower and an avid gardener at home as well. If the above links don't work, then try the overview site. You may also like to look at the thumbnail index. ©1998-2012 All rights reserved.