Winter resistant leaves are leathery, alternate, elliptic or ovate to obovate, 4-10 cm long, apex acuminate or acute, base cuneate to nearly semicircular, margin serrate, front color dark green, back color light, glabrous, petiole thick and short, pilose or glabrous.
The flowers are solitary or 2-3 in the axils of leaves or slightly at the top of branches, with 5-7 petals, pink or reddish in color, notched or concave at the apex, and tube like at the base. Stamens are more developed, the number is up to more than 100, the filament is white, the anther is golden.
It is a round capsule with a woody shell. When it is mature, the capsule will naturally crack and release seeds. The seeds are dark brown or light brown, nearly spherical or polygonal after mutual extrusion. The cuticle is hard.
