Rhizome to 15 cm long, usually cylindrical, sheathed by overlapping leaf bases. Leaves perennial, erect, up to 1.2 m long, glabrous. Scape 0.6–2.5 m tall, hirsute. Inflorescence a dense cylindrical panicle. Tepals bright yellow, narrow spathulate, 12–28 mm long, 8–14 mm wide, the outermost adaxial tepal narrower and shorter than the rest, the upper 5 tepals overlapping, somewhat disjunct from the lowermost tepal; anthers 15–20 mm long; style 13–18 mm long. Seeds oval or reinform, to 5 mm long, densely tomentose. Oct.-Nov.
GipP, HSF. Also SA.
Grown as an ornamental for its large yellow floral displays. In its natural range Wachendorfia thyrsiflora is often a dominant species in permanently moist or marshy habitats throughout the Cape region of South Africa. It is a potentially serious weed, and is naturalised along the Yarra River near Warburton, and around a dam at Emerald.