Vernonia oligocephala is an attractive perennial with bicolored leaves and attractive bright purple flowers. It is the most common silver-leafed species indigenous to the southern African grasslands.
The bicoloured-leaved vernonia is an erect, often tufted herbaceous perennial plant with flowering branches that develop from a woody rootstock. It grows up to 300–800 mm high. The leaves are ovate to lanceolate, up to 40 mm long, dark green on the upper surface and silvery velvety below. Its bright violet flower heads are about 10 mm long and borne in large clusters towards the branch tips. It flowers from August to December.
Vernonia oligocephala is not threatened in its natural habitat.
Distribution and habitat
Vernonia oligocephala is widely distributed in South Africa, it occurs in wooded rocky grassland areas in Mpumalanga, Gauteng, North-West, KwaZulu-Natal and Eastern Cape, and in the neighbouring countries of Zimbabwe and Zambia. It may easily be confused with V. natalensis especially when sprouting after veldfires, as both species occur in the same areas and flower at the same time.
Derivation of name and historical aspects
Vernonia is a genus of about 1 000 species; some species are edible and have economic value. It is named for the English botanist, William Vernon. The specific epithet, oligocephala, means with few heads.
Vernonia oligocephala attracts many insects especially bees and butterflies to its colourful flowers. The light seeds with hairy parachutes are dispersed by the wind. This plant has developed adaptations to the challenges faced by grassland plants such as regular fires; this it achieves through dying back to its underground rootstock during the dry, fire-prone winter months.
Uses and cultural aspects
Vernonia oligocephala is used to make ubulawu, which is the local isiZulu word for plants that cause visionary and prophetic dreams, and allows one to connect with and receive messages from the spiritual world. Its fresh leaves, roots or twigs are pulverized and the infusion is taken orally or used as tea. It is also used as a remedy against mild forms of diabetes.