Commelina africana differs from most other Commelina species by having pretty, small, canary-yellow flowers instead of the usual blue flowers, and also the spathe (bract) is simply folded and not joined.
Commelina africana is a spreading, perennial herb up to 0.5 m high, glabrous or variously pubescent; the rootstock is hard and woody, with hard, thick, long roots. Leaves are variable, oblong to linear, flat or folded, up to 120 mm long but usually smaller, glabrous or glabrescent to variously hairy. Spathes are folded, dry inside, solitary, pedunculate (stalked); apex acute to long acuminate (tapering), often falcate (sickle-shaped). Inflorescence of two cymes (flower clusters) well developed. The flower varies in size, petals yellow. Flowering time: October to March. Commelina africana is divided into four varieties.
According to the SANBI Threatened Plants Programme, Commelina africana is not listed, therefore it is probably not rare or threatened.
Distribution and habitat
Widespread in Africa, Madagascar and the Arabian Pennisula, in forests, savanna and grassland. Very common in southern Africa. The plant is a spreading herb that flourishes in sandy soil in rocky areas where it spreads rapidly.
Derivation of name and historical aspects
The genus Commelina was named after the Dutch botanists Jan Commelijn (1629-1692) and his nephew Caspar (1667/1668-1731). There are ± 170 species occurring in the warmer countries of the world, with 16 species in southern Africa.
The plant grows very well in a wet sandy soils or during good rainfall seasons. The major pollinators of this plant are insects, mainly ants. By using the plants, human beings also contribute to seed dispersal.
Uses and cultural aspects
The Ndebele use a decoction of the roots in the treatment of venereal diseases and as a medicine for women suffering unduly during the menstrual period. The ash of the plant is used as one of the ingredients in a Sotho charm application to the loins for sterility and an infusion is drunk for the same purpose. It can also be burned and the ash is dug in around plants as a fertilizer. Pigs are fed the leaves of this plant. Horticulturally, it is a useful, pretty plant in the garden.
Growing Commelina africana
It is good to cultivate this plant as a decorative flowering plant in your garden or as food for animals such as pigs.
The propagation of this species takes place easily, because even the stem nodes pressed into wet, sandy soil will grow. It is also easy to cultivate from seed. Plant it in a sandy soil or rocky areas. Given more water it will exceed its normal height.
References and further reading
- Leistner, O.A. (ed.). 2000. Seeds plants of southern Africa : families and genera. Strelitzia 10. National Botanical Institute, Pretoria.
- Obermeyer, A.A. & Faden, R.B. 1985. Commelinaceae. Flora of southern Africa 4, part 2: 23-60. Botanical Research Institute, Pretoria.
- Phillips, E.P. 1929. Commelina africana. The Flowering Plants of South Africa 9: t. 321.
- Van Wyk, B-E. & Gericke, N. 2000. People's plants: a guide to useful plants of southern Africa. Briza Publications, Pretoria.
- Watt, J.M. & Breyer-Brandwijk, M.G. 1962. The medicinal and poisonous plants of southern and eastern Africa, edn 2. Livingstone, Edinburgh.
Aluoneswi Caroline Mudau
Pretoria National Herbarium