This well known, drought and wind resistant, indigenous plant can grow into a shrub as it is usually multi-stemmed or a small tree when the lower branches are pruned. It is ideal for water-wise gardens.
Dodonaea viscosa var. angustifolia is an evergreen shrub or small tree up to 5 m high. Its bark is light grey and finely fissured. The droopy leaves are shiny light green above and paler green below. Its flowers are small, yellowish green and are followed by decorative clusters of yellow or reddish fruits with papery wings. Flowers are produced from April to August (autumn–winter). This is a fast growing plant that prefers a sandy substrate; when given good soil and plenty of water it requires minimal water once established.
Left: Dodonaea viscosa var. angustifolia flowers
Right: Dodonaea viscosa var. angustifolia flowers fruit
Dodonaea viscosa var. angustifolia is not a threatened species.
Distribution and habitat
Dodonaea viscosa var. angustifolia grows in a variety of habitats from arid, semi-arid to high rainfall regions and is frost-hardy. It is found in a wide strip along the coast from Namaqualand through the Western Cape, Eastern Cape to KwaZulu-Natal as well as further north in Mozambique and Zambia.
Derivation of name and historical aspects
The genus Dodonaea was named after Rembert Dodoens. He was a Dutch physician and botanist who wrote a book on plants of the Middle Ages. He died in 1585. The specific epithet viscosa means sticky, referring to the young growing tips which contain surface flavonoids; this gives them a shiny appearance. In the genus Dodonaea there are 60 species widespread mostly in Australia. In South Africa there are two recognized taxa: Dodonaea viscosa var. angustifolia and Dodonaea viscosa var. viscosa.
The dense bushy hedges which it may form are ideal bird nesting sites and the flowers attract butterflies. The seed has papery wings and is possibly dispersed by wind.
Uses and cultural aspects
This shrub is grown worldwide, as the roots have soil-binding properties which are effective for the purpose of stabilizing sand dunes and to control erosion. The early Cape settlers used a decoction prepared from the new leaf tips for fever. In the rural areas Dodonaea viscosa var. angustifolia is still widely used for colds, influenza, stomach trouble and measles. For a sore throat and oral thrush it is used as a gargle. The Khoi-Khoi used a concoction of the root for colds and influenza. In Namaqualand the green leaves are boiled slowly, then left to steep, strained, and the extract is used for influenza, colds and also to induce sweating. It also used to relieve coughs and the congested feeling typical of influenza, croup and diphtheria. The same extract is considered to alleviate stomach ailments and fever. The leaves are used externally as a remedy for itchy skin and to treat skin rashes. An extract of the leaves is used as a mild purgative and for rheumatism, sorethroat and haemorrhoids. Other early uses of the plant include the treatment of pneumonia, tuberculosis and skin rashes. In southern Africa it is regarded as one of the most important traditional medicines and is used in combination with other medicinal plants, including Viscum capense (Willem Steenkamp, pers. comm.). Most of the Dodonaea viscosa var. angustifolia specimens found in the Karoo Desert National Botanical Garden are a host plant to the hemiparasitic shrub, Viscum capense which grows on them. Seeds of the parasite are deposited on the branches of the host as a result of birds feeding on the fruits of the parasite and cleaning their beaks on the branches of the host. In arid areas it is also a valuable source of firewood.
Growing Dodonaea viscosa var. angustifolia
As a shrub it can be planted together with other indigenous plants like Gazania krebsiana, a groundcover with orange flowers, and Eriocephalus ericoides, wild rosemary, for a well rounded garden.
Seed can be harvested in autumn and sown in spring into plastic seed trays. A sandy soil mix is used mixed with 10% compost. Dodonaea germinates quite easily, so no special treatment of the seed is needed, and it does well in cultivation. The plastic seed trays are then kept moist and the seeds will germinate in 2–3 weeks' time. When the seedlings are about 100–150 mm tall they are moved to a netted hardening area that gets 30% shade during the day, making them used to more sun.
From there they can grow up to 300–400 mm tall before they are transplanted to 2 L or 4 L bags. As soon as they are transplanted they are moved to areas receiving full sun where they will be buffeted by winds, as in nature, and may be watered as needed.
The Dodonaea specimens are then transplanted to 10 L bags when they are around 1.2 m tall (Geldenhuys, J.pers. comm. 2011).
References and further reading
- Germishuizen, G., Meyer, N.L., Steenkamp Y. & Keith, M. (eds) 2006. A checklist of South African plants. Southern African Botanical Diversity Network Report No 41. SABONET, Pretoria.
- Jackson, W.P.U. 1990. Origins and meanings of names of South African plant genera. University of CapeTown Printing Department, Rondebosch.
- Joffe, P. 2005. Creative gardening with indigenous plants: A South African guide. Briza Publications, Pretoria.
- Van Wyk, B.-E. & Gericke, N. 2000. People's plants: A guide to useful plants of southern Africa. Briza Publications, Pretoria.
- Van Wyk, Braam [A.E.] & Van Wyk, P. 1997. Field guide to trees of southern Africa. Struik Publishers, Cape Town.
- Van Wyk, B.-E., Van Oudtshoorn, B., & Gericke, N. 2009. Medicinal plants of South Africa. Briza Publications, Pretoria.Vlok, J. & Schutte-Vlok, A. 2010. Plants of the Klein Karoo. Umdaus Press, Hatfield, South Africa.
Karoo Desert National Botanical Garden