The Aristea genus comprises about 55 species of evergreen perennials, growing from rhizomes that vary in length. This African genus is most diverse in southern Africa with outlying species found in Senegal and Ethiopia; 45 species occur in South Africa and 7 on Madagascar.
Suitable habitats include high summer rainfall on grassy highlands, rocky outcrops and marshes. Other species favour winter rainfall, montane sandstone habitats. Some flower profusely after fire.
Aristea leaves mostly grow in crowded clusters of basal fans. The leaves are lanceolate, linear or terete (cylindrical), fibrous and without midribs.
The stems are simple or branched, rounded or compressed, two-sided or winged, bearing reduced leaves or leafless except for a small one near the tip.
The flower clusters are borne in two series or reduced to just one or two. Floral bracts are brown or green, membranous or thin and dry within variable spathes. The radially symmetric, star-shaped flowers are often stalkless, coloured blue in variable shades, mauve or white.
The plants display much variation in their pollen, capsules and seeds. The flowers tend to open in the early morning, fading after noon and not lasting beyond a day.
The stamens are erect and free, the anthers oblong to linear. The ovary is oblong or ovoid, positioned between bracts. The style is flexed to the side, topped by a thread-like stigma that is three-lobed or notched. The fruit capsule is ovoid or oblong, three-sided or cylindrical.
Bees visit these flowers much for their pollen. Some species bearing darkly marked flowers in the southwestern Cape are pollinated by monkey beetles. One species produces nectar (Manning, 2009; Leistner, (Ed.), 2000).