Bulbous plant of the Amaryllidaceae family, native to North America, where it is widely spread from the Rockies to the Appalachians, growing in meadows, clearings, and rocky slopes, often at altitude.
Its most distinctive feature is the pronounced curve of its stem at the top, which causes the umbel to droop downward in a nodding attitude — bent, drooping — hence its English vernacular name "nodding onion". The flowers, pink to lilac-pink, are gathered in loose and graceful umbels of 3-5 cm, borne on stems of 30-50 cm, in July-August. The whole has an uncommon lightness and elegance in the genus.
Adapted to a wide variety of conditions, it grows in sun or partial shade, in well-drained to fresh soils, and readily self-seeds. It is suitable for natural borders, prairie gardens, and slopes, and naturalizes easily in infrequently mowed lawns.