- Division: Magnoliophyta
- Class: Magnoliopsida
- Order: Sapindales
- Family: Ruteaceae
- Genus: Calodendrum
- Species: capense
Despite its name, the Cape chestnut tree bears neither true chestnuts nor horse chestnuts. It’s actually more closely related to citrus trees—and if you crush one of this tree’s oil-rich leaves, you’ll be treated to a burst of clean, fresh scent that is something like a cross between lemon and pine.
This native of Africa is best known for its large, showy spikes of pink to mauve flowers that cover the entire crown of the tree during summer. That seasonal floral explosion has made it a favorite ornamental tree, frequently used in landscaping in coastal areas and in warm climates—wherever the winter temperatures don’t dip much below freezing.
The Cape chestnut tree can reach a maximum height of 25 to 40 feet (8 to 12 meters) when it is mature, with a crown that is nearly as wide as the tree is high. When the Cape chestnut's showy flowers disappear, the tree produces bumpy five-lobed fruits that are 1 to 2 inches (3 to 5 centimeters) in diameter—with black half-moon-shaped seeds inside.
Cape chestnut trees can be grown from cuttings or seeds. Young trees grow about three feet (one meter) a year in locations with full sun and protection from wind. Young trees require moderate but regular watering, and they can withstand winter temperatures as low as 25 degrees Fahrenheit (-4 Celsius).
Currently, some California nurseries have stopped selling Cape chestnut trees for landscaping, because the trees can serve as hosts to the Asian citrus psyllid, an insect that can carry citrus greening disease (Candidatus Liberibacter asiaticus). This disease has devastated millions of acres of citrus crops worldwide and has been found not only in California, but also in Florida, Georgia, Louisiana, South Carolina, Texas, Puerto Rico and the US Virgin Islands.
Wood from the Cape chestnut tree is used in home construction in Africa. Furniture, tool handles, and yokes are also crafted from the wood. In addition, Cape chestnut wood is used as firewood and to make charcoal. An oil derived from the Cape chestnut seed—yangu oil— is an ingredient in skin care products and lotions, soap, and biofuels.
At the Safari Park, you’ll find a large Cape chestnut tree in Nairobi Village. It puts on an impressive flower show in summer, and the tree is still beautiful when it drops its leaves for winter.