Tree 7–18 m. tall with much-branched rounded crown.. Leaves subopposite, oblong or oblong-lanceolate, up to 30 cm. long, 9 cm. wide.. Flowers large, mauve or pink, 5–7.5 cm. in diameter, in large elongate terminal panicles.. Calyx conspicuously ribbed, rusty or grey-velvety.. Petals 3.2–3.5 × 2.1–2.5 cm., with claw 5–6 mm. long.. Capsule 1.7–2 cm. long.