Hemizygia obermeyerae is a fast growing, much branched shrub which can grow to 1,8m tall. It is covered with velvety hairs throughout. The broadly ovate to ovate - lanceolate leaves are up to 60mm long and 18 - 30mm in width. The leaves are strongly and pleasantly aromatic and have short petioles. The showy, two-lipped tubular flowers are mauve pink and appear from summer into autumn (December - April), making this a very rewarding plant in the garden.

The genus name Hemizygia is derived from the Greek words, hemi - meaning half and zygon - meaning a yoke or join. The species name obermeyerae commemorate Miss Amelia Obermeyer (later to become Mrs. Amelia Mauve) a botanist at the National Herbarium, Pretoria, who first collected this plant in 1931. The plant was described by Ashby in the Journal of Botany (London) in1935.

Hemizygia obermeyerae is restricted to the Northern Province from the Soutpansberg southwards to just north of the Abel Erasmus Pass in the Northern Drakensberg mountain range.

Hemizygia obermeyerae grows in grasslands, rocky hillsides and along forest margins. It grows in acidic quartzitic sandstone soil, at an altitude of 1400 - 1800m with a high rainfall of more than 1250mm per annum. Hemizygia obermeyerae resprouts after fires in grass, lands and is pollinated by bees and other insects.

In the garden this plant can be used as a shrubby border, or individually as a specimen plant. It can also be used as a low growing hedge.

Growing Hemizygia obermeyerae

Hemizygia obermeyerae is a rapid grower, gaining popularity in South Africa. It can withstand mild frost provided it get additional water. It also need to be well watered in the drier and hotter central regions of the sub continent. In the summer rainfall areas, it requires additional watering in the winter months. This plant need to be pruned in winter, after flowering to ensure a denser and more floriferous shrub. No pruning is needed in the growing season. A compost dressing with additional fertilizer like 2:3:2 in spring (September - November) and summer (December - March) will be beneficial to the plant. Hemizygia obermeyerae can be propagated by herbaceous cuttings taken during late summer, or by seed. Rooting of cuttings should be carried out in bottom heated mist-propagation beds. This plant is relatively pests and disease free.

The Lamiaceae, sage family, consists mainly of perennial herbs and shrubs, usually aromatic. It comprises about 170 genera and 500 species worldwide, in warm and temperate regions, of which 37 genera and over 250 species occur in South Africa.

This genus, Hemizygia, consists of 28 species widely distributed in the summer rainfall, eastern parts of South Africa.

Ebrahim Lawrence
Kirstenbosch Botanic Garden
March 2001