This species is a large deciduous tree which forms a pyramidal habit. It may reach 30 to 35 m (98 to 115 ft) in height in its natural habitat, but is usually shorter in cultivation. The trunk is smoothly cylindrical and green or grey-green in colour, often tapering unbranched to the very tip of the tree. Leaves have long petioles and measure up to 30 cm (12 in) x 25 cm (9.8 in), are glossy green, glabrous, simple, alternate, and highly variable in shape - they may be entire and ovate or up to 5-lobed.
Flowers are bright red or scarlet in colour, bell-shaped when viewed from the side and star-shaped when viewed end-on, about 25 to 30 mm (0.98 to 1.18 in) long by 16 to 22 mm (0.63 to 0.87 in) wide, and are produced on large panicles. They have five petals, fused at the base and free at the ends. The ensuing fruits are a dehiscent pod which is dark brown, leathery, boat-shaped and about 10 cm (3.9 in) long. They ripen around May to August in Australia, splitting along one side to reveal two rows of yellow seeds numbering 12–26, each around 10 by 5 mm (0.39 by 0.20 in) and surrounded by a papery aril covered in stiff hairs which are very irritating if touched.