Erect to prostrate perennial herb, 20-60 cm long, often dichotomously branched from the base, glabrous to pubescent, rooting below, often developing subterranean or concealed, whitish flowers on underground scapes developed from the lower nodes. Leaves ovate to ovate-oblong, subsessile to shortly petioled, with sheathing base, 2.5-7.5 cm long, 1.5-3.5 cm broad, entire, acute to sub-rounded at apex; petiole 4-10 mm long; sheaths 1-2 cm long, ciliate on the margins. Upper cymes 2-3-flowered, lower 1-2-flowered, sometimes suppressed. Aerial flowers blue, in short cymes subtended by spathes, maturing earlier than the subterranean flowers. Seeds rugose or closely pitted, sometimes wanting in aerial flowers.