Allium  

Herbs perennial, bulbiferous, sometimes with well-developed, thick or thin rhizomes, rarely with stolons or tuberous roots, usually with onionlike, leeklike, or garliclike odor when fresh. Bulb covered with a tunic. Leaves sessile, very rarely narrowed into a petiole, with a closed leaf sheath at base, linear, linear-lanceolate, or lorate to orbicular-ovate, cross section flat, angled, or semiterete to terete, fistulose or solid. Scape terminal or lateral, sheathed or naked. Inflorescence a terminal umbel, sometimes with bulblets, rarely flowerless and with bulblets only, enclosed in a spathelike bract before anthesis. Pedicels with or without basal bracteoles. Flowers bisexual, very rarely degenerating into unisexual (when plants dioecious). Perianth segments free or united into a tube at base. Filaments usually connate at base and adnate to perianth segments, entire or toothed. Ovary with 1 to several ovules per locule; septa often containing nectaries opening by pores at base of ovary. Style simple; stigma entire or 3-cleft. Capsule loculicidal. Seeds black, rhomboidal or spheroidal.