Disa purpurascens is a species of orchid found in South Africa (SW. Cape Prov.). It is also known as the early blue disa or the bloumoederkappie.
Plants are NaNmm tall, growing from a tuber with a length of about 30mm and a diameter of about 10mm. About 10 narrow, rigid leaves, about half as tall as the plant, grow from a basal rosette. The base of the plant is often surrounded by a sheath of old leaf fibers.[1] This species flowers in October and November, producing an inflorescence of 1–7 sweetly scented flowers. Each flower has a blue hood and side wings, with a dark purple lip below. Yellow-green petals are found at the back of the hood.[2] While the flowers look similar to those of Disa graminifolia, they differ in having an upcurved lip margin and a conical spur. They also flower at different times of the year.[3] While there is generally very little variation between plants, some white flowers have been observed. This has been suggested to be a recessive condition.
This species has a fairly narrow distribution, growing in coastal regions between Cape Hangklip and Cape Agulhas. It is not thought to occur above 100m (300feet) above sea level.