Hibiscadelphus hualalaiensis, of the Malvaceae (mallow) family, is a tree 5 to 7 m (16 to 23 ft) tall with the trunk up to 30 cm (12 in) in diameter and whitish bark. Leaves are heart-shaped and 10 to 15 cm (4 to 6 in) long with a broad tip, a notched base, stellate hairs, and stalks 4 to 10 cm (1.5 to 4 in) long. One or two flowers are borne in the axils of the leaves and have stalks 1.5 to 14 cm (0.6 to 5.5 in) long. Five toothlike bracts are borne below each flower and the calyx is tubular or pouch-like. The overlapping petals form a curved bisymmetrical flower with longer upper petals, typical of bird-pollinated flowers. The flowers are greenish yellow on the outside and yellowish green, fading to purplish within, and 2 to 5.5 cm (0.8 to 2.2 in) long. The fruit is woody and the seeds have a dense covering of hairs.