An evergreen perennial herb forming loose tussocks with well-developed rhizomes. Leaves are long and narrow (25–80 cm × 1.2–1.8 cm), green to dark green with distinct darker margins, upright to arching or drooping, smooth and somewhat glossy. The inflorescence is an erect to spreading panicle up to 1 m tall, with small nodding flowers (c. 9–11 mm) that open in the morning and wither by late afternoon. Sepals are olive-green flushed red-brown, petals white with a green midvein. The fruit is an ovoid to oblong berry (8–20 mm), grey-white to violet-blue, often glossy, containing shiny black seeds.