Allium sphaerocephalon, also known as the Round-headed Leak, is a summer flowering Allium with egg shaped heads about 24" (60cm )tall.which are initially completely green, but the whole head then turns deep reddish purple starting with the tip, The intermediate state with purple and green is we think the most interesting. Insects love them and a small thicket is a great sight adding colour, movement and interest. The shape goes well with some of the similarly spiky Sea Hollies.
Allium sphaerocephalon bulbs should be planted 3" (7.5 cm) deep in a sunny spot in well drained soil and about 3-4" (7.5-10 cm) apart. Such small bulbs are amazing in their abiliy of doing so well. Interplant them amongst your summer flowering plants to weave things together.