The genus Vernonia is named after William Vernon, died 1711, an English botanist who collected in Maryland in the late 1600s. Vernonia is a large genus of over 1000 species of forbs and shrubs in the family Asteraceae. There are approximately 40 in southern Africa, occurring throughout southern Africa but not in the winter-rainfall region. Some species are known as ironweed. Some species are edible and of economic value. They are known for having intense purple flowers. Species of this genus are found in South America, Africa, Southeast Asia, and North America. Vernonia species are well known for hybridizing between similar species in areas of overlapping ranges.

Vernonia mespilifolia is a South African indigenous species from the Eastern Cape, KwaZulu-Natal, Limpopo, Mpumalanga and Western Cape Provinces. It is synonymously known as Gymnanthemum mespilifolium and Cacalia mespilifolia. Vernonia mespilifolia grows into a scrambling shrub. From summer to autumn it bears flowers that are mauve to start but fading to white. It is usually found growing on forest margins.