Allium cernuum is a herbaceous perennial growing from an unsheathed elongated conical bulb which gradually tapers directly into several keeled (thin and flat) grass-like leaves, 2–4 millimetres (3⁄32–5⁄32 inch) in width.

[5] The flowers mature into spherical crested fruits which later split open to reveal the dark shiny seeds.

[14] The species has been reported from much of the United States, Canada and Mexico including in the Appalachian Mountains from Alabama to New York State, the Great Lakes Region, the Ohio and Tennessee River Valleys, the Ozarks of Arkansas and Missouri, and the Rocky and Cascade Mountains of the West, from Mexico to Washington.

It has not been reported from California, Nevada, Florida, Louisiana, Mississippi, New Jersey, Delaware, New England, or much of the Great Plains.

It is absent from North Dakota and most of the Great Plains states and intermountain region of the U.S.[5] In Minnesota it is listed as a threatened species.