Approximately 700 species of perennials from the northern hemisphere, mainly the temperate zone. Most species have bulbs though in some these are cylindrical or leek-like, some are also rhizomatous. The leaves are usually linear, either flattened, keeled or tubular but in some species they are lanceolate or elhptic. In many of the summer-blooming species they are starting to, or have totally withered, when the flowers are at their best. This can somewhat detract from the floral display unless the bulbs are sited amongst low growing plants to mask this unfortunate habit. Each flower is composed of six tepals which may spread out like the rays of a star, or point forwards to form a cup, bowl or bell. They are arranged in terminal umbels which are often but not invariably dense and globe-shaped. In some species small bulbils are mixed with, or replace the flowers. Most species smell of onion or garlic when bruised.
Many of the smaller species are suited to the rock garden or alpine house and a few are particularly desirable. All thrive in ordinary fertile, well drained but not dry soil, and a modestly sunny site; some tolerate shade. Many allium names are to be found in the seed lists of societies and botanic gardens. Not all those dealt with here are particularly decorative and some are best avoided. Propagation by division or offsets when dormant or seeds in spring.
a, A. cernuum; b, A. farreri; c, A. moly; d, A. insubricum; e, A. sikkimensis;