Allium nigrum, common name black garlic, broad-leaved leek, or broadleaf garlic, is a plant species commonly cultivated as an ornamental. It is unusual in the genus in that it lacks the onion or garlic scent shared by most of the 900 accepted species in the group. The species is native to the Mediterranean region but cultivated as an ornamental in many other places. It has become naturalized in some regions, including parts of the United States (especially Washington and Oregon).
Allium nigrum produces asymmetric bulbs up to 5 cm across. Each plant has 3-6 leaves, each flat, up to 60 cm long and 2.5 cm across. Scapes are round in cross-section, up to 100 cm tall. Flowers up to 9 mm across; tepals white with a green midevein; anthers purple or yellow.
^Hitchcock, C. H., A.J. Cronquist, F. M. Ownbey & J. W. Thompson. 1969. Vascular Cryptogams, Gymnosperms, and Monocotyledons. 1: 1–914. In C. L. Hitchcock, Vascular Plants of the Pacific Northwest. University of Washington Press, Seattle.