Haunting rich purple flowered form of a rarely offered nodding onion from moist woodlands of East Asia. It's also one of the latest blooming alliums -- typically in late summer and early fall.
Deep 3.5-inch pots. Zone 5. Photo: Jenny Wainwright-Klein, https://nargs.org/photo/allium-macranthum
Part shade; moist humus-rich soil; 18x12"; late summer to fall