Brachychiton bidwillii Seeds | Little Kurrajong

Little kurrajong in flower, deep pink bell blooms clustered on bare slender stems — Little Kurrajong (*Brachychiton bidwillii*): Malvaceae, the smallest of the Australian kurrajongs, flowering on bare wood.

LATIN NAME: Brachychiton bidwillii

COMMON NAME: Little Kurrajong

Plant Profile

Little kurrajong is the smallest of the Australian bottle trees, and that is the first thing that makes it useful in a small garden. It grows as a sparse, open shrub or small tree, usually one to three metres and rarely more than four, with a swollen base, a few angular branches and leaves that are large, lobed and often dropped before the plant flowers.

Flowering is the event. The tree loses most of its leaves in the dry season and then covers its bare branches with clusters of bell-shaped flowers, deep pink to brick red, five centimetres long and held in the leaf axils and along the older wood. The effect is of a shrub decorated rather than grown. The fruit is a woody, boat-shaped follicle that splits to release seeds in a papery yellow lining, and inside that lining are stiff hairs that irritate skin and throat.

Science & Biotechnology

The genus Brachychiton is Australian and Papuan, and it is placed in the mallow family in the broad sense, having formerly stood in Sterculiaceae. Its species share a capacity for storing water in swollen trunks and roots, an adaptation to the alternating wet and dry seasons of their habitat, and little kurrajong takes that strategy to its smallest scale, with a tuberous root that can be several times the volume of the top growth.

The flowering habit is cauliflorous in the loose sense: flowers are borne on old wood and on the trunk as well as on young shoots, which puts them where pollinators can find them when the plant is leafless. Pollination is by bees and small beetles. The seed coat is hard and impermeable, and in the wild germination follows fire or a long wet period that softens the coat, so the seed can sit in the soil for years before a season suits it.

Uses & Benefits

This is a plant for small gardens in warm, dry climates, where its size makes it practical in a way that the Illawarra flame tree is not. It fits into a gravel garden, a courtyard or a native planting bed, needs no irrigation once established, and flowers well in a pot, which few trees of the genus will do. The shape is architectural rather than lush, and it looks best against a wall or a hard surface.

The seeds were eaten by Aboriginal people after careful preparation: the follicles were collected, the irritant hairs removed, and the seeds roasted or pounded into a paste. That is a food of last resort rather than a staple, and the hairs make careless handling unpleasant, so the seed is best treated as a propagation material rather than a crop. The plant has no significant commercial use beyond horticulture.

Growing from Seed

The seed coat must be broken before water can get in. Nick each seed with a file or rub it on sandpaper until the pale layer shows, then soak in warm water for twelve hours; the seed will swell visibly. Sow in a gritty, free-draining mix at twenty-five to thirty degrees, barely covered, and keep moist but never wet.

Germination is usually within three to six weeks and can be very uneven. The seedlings develop a swollen root quickly and should be potted into deep containers so it has room. Grow them on in full sun, water sparingly, and plant out once the root has filled the pot, in a warm, well-drained site with shelter from frost while young.

Our Take

The kurrajong for a small space: drought-hardy, oddly beautiful, and flowering when it has nothing else to show. Plant it where the trunk can be seen, because the flowers come out of the wood.

Tree Seeds