Brachychiton is a genus of 30 or more species, most of which occur in tropical parts of Australia in dry areas or in rainforest. They are large shrubs or trees. One of the most commonly cultivated is the Illawarra flame tree (Brachychiton acerifolius) which is popular due to its spectacular crimson flowers.
The Black Kurrajong or, more commonly, just Kurrajong (B.populneus) is widely distributed in nature and is also common in cultivation. It is a small to medium-sized tree which may reach 20 metres in height although it is often much smaller. It has a compact and densely foliaged habit which makes for an attractive specimen plant in a large garden or park.
The trunk is stout and grey, while the leaves are shiny green and either entire or 3 lobed, up to 10cm long. Young foliage is pale green tinged with pink, which can give the tree an interesting appearance. The small bell-shaped flowers are cream with a pink,red or purple tinge. The flowers are followed by large, boat-shaped seed capsules which contain many large seeds, similar to corn kernels.
B.populneus is commonly cultivated and is hardy in a range of climates and soils. At least three hybrids with B. acerifolius are known and have been brought into cultivation – B. x roseus, B. ‘Jerilderie Red’ and B. ‘Froggatt’s Pink’. All have some of the flowering qualities of their famed Illawarra Flame Tree parent plus more persistent, attractive foliage from the Kurrajong parent.
The tree is quite popular in farming areas as it can be used as fodder during drought periods. It is often seen preserved in paddocks and fields and it provides dense shade beneath it for stock.
Propagation from seed is relatively easy without any pretreatment. The seeds are surrounded in the capsule by irritant hairs and are best collected using gloves.
Photo: Keith Townsend
Kurrajong seeds (with attendant Harlequin bug)
Photo: Heather Knowles