Description from Flora of China
Evergreen shrubs to 1 m tall; branches glabrous, many lenticellate, often much branched. Leaves opposite, rarely alternate or nearly 3-worled; stipules ovate, ca. 1 mm; petiole 3-13 mm, eglandular at apex; leaf blade narrowly elliptic or oblong, 6-14 × 2-4 cm, papery, glabrous, green adaxially, purple or dark red abaxially, or green or greenish abaxially when old, base attenuate, margin serrulate, apex long acuminate; midvein convex on both surfaces, lateral veins 8-12. Flowers dioecious in axillary or terminal racemes; male inflorescences 1-2 cm, female ones 3-5-flowered, slightly shorter than male. Male flowers: pedicels ca. 1.5 mm; bracts broadly ovate, ca. 1.7 × 1.7 mm, serrulate inside base, 2-glandular, each bract 1-flowered; bractlets 2, linear, ca. 1.5 mm, lacerate-serrulate on upper part, 2-glandular at base; sepals 3, lanceolate, ca. 1.2 mm, serrulate at apex; stamens exserted from calyx; anthers rounded, slightly shorter than filaments. Female flowers: pedicels strong, 1.5-2 mm, bract and bractlets as in male; sepal 3, slightly connate at base, ovate, ca. 1.8 × 1.2 mm; ovary globose, glabrous; styles 3, free or ± connate at base, ca. 2.2 mm. Capsules globose, ca. 8 mm in diam., truncate at base, concave at apex. Seeds nearly globose, ca. 2.5 mm in diam. Fl. almost throughout year. 2n = 22.
Evergreen or deciduous forests, secondary forests, thickets, also cultivated; below 1500 m. Fujian, Guangdong, Guangxi, Hainan, Taiwan, Yunnan [Laos, Malaysia, Myanmar, Thailand, Vietnam; originally from Vietnam, widely cultivated].