Succulent plant with thick rhizome from which a terminal cluster of erect or suberect leaves arise. Leaves to c. 40 x 6 cm, sword-like, glossy purple beneath, glossy dark green above. Inflorescences congested and enclosed by large boat-shaped spathes, on peduncles to 4 cm. Bracts glossy deep purple, usually c. 2.5 cm deep and 6 to 7.5 cm wide, each end being attenuated. Perianth white, open in mornings. Corolla white; tube slender, 15-17 mm long; lobes equal or nearly so, 7-8 x 6-7 mm, broad ovate with obtuse apex. Filaments and beard white. Flowers ephemeral, shrivelling by middle of day. Several metres along bank with numbers of plants altogether.