About 100 species of bulbous perennials from central and western Asia, with several in Europe and one eastwards to Japan (the latter now sometimes classified in the genus Amana). Each mature bulb usually produces one stem bearing a few sessile linear to ovate leaves and topped by usually one flower, but up to six or more in some species. Each flower has six similar tepals forming a cup, which may open out on warm sunny days, a central, erect, more or less cylindrical ovary bearing a large sessile stigma and six prominent stamens.
All but the tallest species are suitable for the rock garden, raised bed or alpine house. Well drained soil and a sunny site are basic requirements. Most species appreciate a dry summer rest, and in heavier soils and higher rainfall areas it is advisable to lift as the foliage fades, and store the bulbs dry until late autumn. Propagation by seed in spring or natural multiplication of the bulbs which can be separated when dormant. (Flowers solitary and spring-opening unless stated otherwise)