Rhodocoma capensis Steud.
A very elegant reed-like plant with slightly arching branches which have whorls of finely divided, feathery looking foliage. This species can be grown as part of a mixed border or in containers and grows to a height of 1 to 2 m.
Tufted, compact plants of 1 to 2 m high, the diameter at the base growing up to 1 m. The stems are quite sturdy and have distinct nodes like a bamboo. At each node there is a thick whorl of finely divided, fertile branches, giving the whole plant a feathery appearance. The colour of the foliage-like branches is a deep green with small brown inflorescences at the tips. The growth form of this species is quite unique in that all the branchlets are fertile, in contrast with other restios where the finely divided side stems are not fertile. The branches are slightly arching and this gives the plants a very elegant appearance. The plants can reach a height of 1 to 1.5 m in three years and with age become slightly more upright and can reach a height of 2 m after five to seven years. Male and female plants flower sporadically from September to November, the female flowers are a deep pink, whereas the male flowers are pale yellow-green.
Distribution and habitat
This is a very widespread species and can be found along roadsides, streamsides, in little pockets of soil in between rocks, and in damp loamy soils from the Cederberg in the Western Cape all along the inland margins of the Cape Fold Mountains to Grahamstown in the Eastern Cape. Driving through the Little Karoo in a very dry and hot landscape, it is quite surprising to find a soft-looking restio like Rhodocoma capensis growing in a drainage ditch along the road, covered in red dust. It is a very hardy and tough species, and very adaptable. The plants have proved hardy in cold climates, withstanding temperatures of - 7 ºC when provided with good protection in the form of a deep layer of mulch.
Derivation of name and historical aspects
The species name capensis refers to the fact that this plant can be found throughout the southern part of South Africa, the old Cape Province. It is part of the large family of Restionaceae, a southern hemisphere family of more than 400 species of about 40 genera in southern Africa, Australia, Madagascar, Indo-China and Chile. About 320 species occur in South Africa, most of them in the Cape Floristic Region. Rhodocoma is a relatively small genus with six described and published species, R. gigantea and R. capensis being the best known. Thamnochortus insignis is the best known restio in South Africa for its widely used, long-lasting thatching material.
Like all other Restionaceae, Rhodocoma capensis is wind pollinated. The seeds are very small and look like tiny dark brown nuts. When the seeds are ripe, they fall on the ground and remain in the top layer of the soil till the circumstances are right for germination, normally during autumn after a fire. An interesting observation is that the very different looking male and female flowers are most visible during soft, soaking rains or a fine drizzle when they flower during the late spring. This might be to improve the pollination process because the pollen becomes heavier when moisture-laden and is distributed as it were, close to home. This is one of the few restios that has striking flowers, they are small but of a deep pink colour in the female plants and light yellow-green in the male plants.
Since its introduction into the horticultural market, Rhodocoma capensis has proved to be a popular plant for gardens and large formal plantings, with its elegant, evergreen appearance. This is the most commercially useful aspect of the species as the foliage is too soft for the traditional use as a broom, while the high tannin content of the plant makes it unpalatable for animals except for the very young growth.
Growing Rhodocoma capensis
Rhodocoma capensis is best grown from seed. The seed is very difficult to collect in large quantities as it is very small and is released by the plants as soon as it is ripe. By the time the seeds are ripe it is also difficult to differentiate between the male and female plants. However, the germination rate of Rhodocoma is very high, up to 80% when the seed is sown at the right time of the year and treated with smoke or a solution of smoke water. The seed should be sown in autumn or early spring when the night temperature is around 10 º C and the day temperature 15º C higher.
Division of the plants is not easy, the plants can only be divided in quite large pieces and re-growth is slow. This should be done during the cold winter months or during late winter/early spring in the northern hemisphere. Rhodocoma capensis can be planted in large groups in formal plantings, in mixed borders or in containers. The plants should be well mulched with pine bark or any other kind of rough mulch and can be fed occasionally with an organic fertilizer. They need to be watered regularly. When the plants are planted in the right place, in full sun and with plenty of air movement around them, they are very hardy and do not seem to suffer from many pests or diseases. The only pest this species seems to suffer from now and again is a small spider or mite which spins a web around a bunch of stems. If the web is not removed by hand as soon as possible, that part of the plant dies back.
- Brown, N., Jamieson, H. & Botha, P. 1998. Grow restios. Kirstenbosch Gardening Series. National Botanical Institute, Cape Town.
- Dorrat-Haaksma, E. & Linder, H. P. 2000. Restios of the Fynbos. The Botanical Society of South Africa, Cape Town.
- Goldblatt, P. & Manning, J. 2000. Cape plants. A conspectus of the Cape flora of South Africa. Strelitzia 9. National Botanical Institute, Pretoria.
- Linder, H.P. 1985. Conspectus of the African species of Restionaceae. Bothalia 15: 387-503.
- Linder, H.P. 1991. A review of the southern African Restionaceae. Contributions from the Bolus Herbarium No. 13.
- Smith. C.A. 1966. Common names of South African plants. Memoirs of the Botanical Survey of South Africa No. 35.
Kirstenbosch National Botanical Garden
Plant Type: Restio
SA Distribution: Eastern Cape, Western Cape
Soil type: Sandy, Loam
Flowering season: Spring
PH: Acid, Neutral
Flower colour: Brown, Pink
Aspect: Full Sun
Gardening skill: Average