Description from Flora of China
Shrubs 0.5-1.2 m tall. Branchlets nearly 4-angled to terete, pubescent when young, glabrescent. Petiole 3-17 cm, pubescent to tomentose; leaf blade broadly ovate to sub-cordate, 9-22 8-21 cm, abaxially pubescent especially on veins and with several large glands near base, adaxially strigose, base truncate, broadly truncate, or subcordate, margin sparsely irregularly dentate, apex acuminate. Inflorescences terminal, dense corymbose cymes; peduncle tomentose; bracts lanceolate, 1.5-3 cm; pubescent, with several large glands. Flowers single or double, fragrant. Calyx 1.5-2.5 cm, deeply 5-lobed, pubescent, with several large glands; lobes linear-lanceolate or lanceolate, 0.7-1.6 cm. Corolla white, pinkish, or red, lobes elliptic or ovate.
* Wild in Guangxi, Guizhou, and Yunnan [cultivated in tropical and subtropical Asia]