About Disa purpurascens Bolus
Disa purpurascens Bolus plants grow to between 200 and 250 mm (7.9 to 9.8 inches) tall from a tuber that is roughly 30 mm (1.2 inches) long and 10 mm (0.39 inches) in diameter. A basal rosette produces around 10 narrow, rigid leaves that reach about half the total height of the plant. The base of the plant is frequently surrounded by a sheath made of old leaf fibers. This species blooms in October and November, producing an inflorescence that holds 1 to 7 sweetly scented flowers. Each flower has a blue hood and blue side wings, with a dark purple lip positioned below the hood. Yellow-green petals grow at the back of the hood. Though the flowers of Disa purpurascens resemble those of Disa graminifolia, they can be distinguished by their upcurved lip margin and conical spur. The two species also flower at different times of the year. There is typically very little variation between individual Disa purpurascens plants, but rare white-flowered individuals have been observed; this white-flowered trait is thought to be a recessive genetic condition. This species has a relatively narrow distribution range, growing in coastal areas between Cape Hangklip and Cape Agulhas. It has not been recorded growing at elevations above 100 m (330 ft) above sea level.
