Plum-colored starling weigh 45 g and the sexes are dimorphic in plumage. The males upperparts, including the chin, throat and wings are iridescent purple. The underparts are pure white. The coloration varies from dark to rosy depending on the light. The bill and legs of the male are black, the eyes has a yellow outer ring around a brown centre.
The female lacks any of the iridescent plumage. The forehead to nape and the sides of the head is brown with a dark central streak on the feathers. The mantle, rump, wings and tail of the female are a dark brown with paler margins.
The primary feathers have rufous-brown inner webs. Her underparts are white with dark central streaks, which are broadest on the breast. The plum-colored starling female's bill and legs are black, her eyes has a yellow outer ring with a brown centre.
Plum-colored starling are monogamous and solitary breeders. Their breeding dates are from October to January in Zimbabwe and South Africa and October to February in Botswana. Both sexes carry in green leaves and other material to build the nest.
The nests are usually build in a tree hole, 2 to 6 m above the ground. The nests are also built in hollow fence posts. Dung is used in the base of the nest, it may form as part of a platform in a deep hole. 2 to 4 eggs are usually laid. They are a pale blue colour with spotted reddish-brown colouration on the thicker end of the egg. Incubation is done by the female only for a period 12 to 14 days.