Calodendrum capense (Cape chestnut)
Flowers of Calodendrum capense (Cape chestnut) (Photo: Andrew Massyn)
Calodendrum capense (L.f.) Thunb.
Least Concern (LC) according to IUCN Red List criteria; widespread and locally common.
Upland evergreen forest; lowlands to sea level in South Africa.
Timber, ornamental, cosmetics.
About this species
Despite its common name, Cape chestnut is not closely related to chestnuts (Castanea species) or horse chestnuts (Aesculus species), but instead is a member of the citrus family (Rutaceae). It is not a typical citrus in appearance, as it is a large tree, with spectacular flowers, and the fruit does not look like those of its relatives (such as lemons, oranges and limes). It looks spectacular when in flower, as the large, pink flowers cover the whole of the crown (the leafy part of the tree).
Carl Thunberg (1743-1828), a Swedish physician and botanist who was a protégé of Carl Linnaeus (the father of modern taxonomy), saw this tree in South Africa in 1772. He was taken with it and gave it the generic name Calodendrum, which is derived from the Greek for ‘beautiful tree’.
Geography and distribution
From the highlands of Ethiopia, the distribution of Cape chestnut follows the mountains of East Africa to the lowlands of the Cape. It is found in Ethiopia, Kenya, Uganda, Tanzania, Malawi, Zimbabwe and South Africa.
Overview: A tree growing up to 7–20 m tall.
Leaves: Smooth and aromatic with scattered, translucent dots; about 14×8 cm and borne opposite each other on the stem.
Flowers: Pink and mauve flowers are produced in large, terminal sprays, often covering the whole canopy of the tree. Each flower has five spreading petals measuring up to 3.5×0.7 cm. The stamens (male, pollen-bearing parts) are as long as the petals.
Fruit: A round, warty capsule, splitting into five sections to release the ten black, angular seeds.
Threats and conservation
Cape chestnut has been assessed as Least Concern because it is widespread and can be locally common in drier upland forest as well as in forest margins and scrub in the south of its range.
The wood is hard and pale in colour. It is easily worked, bends well, and is used widely for furniture, flooring, tool handles and implements. The bark is widely used as an ingredient in cosmetics (some of which are used to dye the skin whitish), and the seed oil is used in soap-making. The seeds are readily eaten by birds and monkeys.
Millennium Seed Bank: Seed storage
The Millennium Seed Bank Partnership aims to save plant life worldwide, focusing on plants under threat and those of most use in the future. Seeds are dried, packaged and stored at a sub-zero temperature in our seed bank vault.
A collection of Calodendrum capense seeds is held in Kew’s Millennium Seed Bank based at Wakehurst in West Sussex.
Cape chestnut is a popular ornamental in eastern and southern Africa and is easily grown from seed or cuttings. Young trees can grow a metre a year and transplant well.
This species at Kew
Specimens of Cape chestnut wood and bark are held in Kew’s Economic Botany Collection in the Sir Joseph Banks Building, where they are available to researchers by appointment.
Coates Palgrave, K. (2002). Trees of Southern Africa, 3rd Edition. Struik Publishers, Cape Town, Johannesburg.
Kalema, J. & Beentje, H. (2012). Conservation Checklist of the Trees of Uganda. Kew Publishing, Royal Botanic Gardens, Kew.
Kokwaro, J. O. (1982). Rutaceae. In: Flora of Tropical East Africa, ed. R. M. Polhill. Balkema, Rotterdam.
Notten, A. (2001). PlantZAfrica - Calodendrum capense. Available online (accessed April 2012).
Kew Science Editor: Henk Beentje
Copyediting: Emma Tredwell
Although every effort has been taken to ensure that the information contained in these pages is reliable and complete, notes on hazards, edibility and suchlike included here are recorded information and do not constitute recommendations. No responsibility will be taken for readers’ own actions.