Plants 1-3 m, much branched. Petiole 0.8-2.5 cm; leaf blade 10-20 × 3-7 cm, base broadly cuneate to rounded, margin crenulate-serrulate, apex long acuminate, adaxially rugulose and puberulent, abaxially densely-tomentose to lanate-tomentose. Panicles 10-15 cm, branches 4-7 cm; verticillasters 10-18-flowered, globose; bracteoles ca. 1 mm, densely tomentose outside, glabrous inside. Flowers ca. 2 mm. Pistillate flowers: calyx campanulate, ca. 1.5 mm, to 6 mm in fruit, tube very short, becoming conspicuously ribbed; teeth subulate, later spinescent, ± purple. Corolla tube puberulent, lower lip slightly longer than upper lip, with middle lobe ovate. Stamens inserted on apical part of tube, included. Style 2 × as long as corolla. Bisexual flowers: calyx minute, ca. 0.6 mm. Corolla to 3 mm; upper lip ovate-oblong, ca. 0.5 mm, straight, emarginate; lower lip elongated, spreading, ca. 1.5 mm, middle lobe ovate-oblong, 2 × as long as ovate lateral lobes. Style erect, slightly longer than corolla. Nutlets obovoid, ca. 1 mm, yellow-brown, with a small basal white scar. Fl. Jan-Mar, fr. Mar-Apr.