This is a lovely candelabra allium with drooping bell flowers in intermingling muted shades of mauve green and cream. Nectar oozes from them, and once pollinated they close up into erect arrowhead seed heads, which are great for flower arranging. 

Leaves are mid green and straplike, and stems tall and brittle - try to use other plants for extra support. Partial shade and moist well-drained soil are also preferred. 

Propagate by replanting offsets or seeds in autumn, or allow to self seed.