Perennial herb, 0.6-1.5 m; rhizome stout, corm-like, moderately branched, rugose. Leaves striate, suberect, basally expanded; sheaths firm, reddish brown, fibrous. Peduncle terete or flat, smooth. Spathe conspicuous, ± fibrous, subtending inflorescence. Bracts closely imbricate, lower ones broadly lanceolate; upper ones tubular, sheathing ovary and eventually fruit. Inflorescence composed of 3-30 cymes; cyme cylindrical to acuminate; single flower per cyme in axils or rarely 2 or 3 developing from base to apex; perianth tube 4-7 mm long, rarely absent; lobes yellow. Flowering time Jan., Dec. Capsule obovoid, glabrous, smooth, dark brown.
Rhizomatous perennial, 50-110 cm. Leaves terete to linear, spathes fibrotic, dilated. Flowers in a dense inflorescence of (3-)8-30 cymes, yellow, with a perianth tube.