Allium Hollandicum Purple Sensation - Ornamental Onion
There are masses of these growing mainly under the silver birch at the Back right corner of the garden near the gravel seating area. They look stunning in late spring. They will multiply, so to prevent them self seeding, I cut the spent flower heads off. They are bulbs, so if they get too much...simply dig them out and green bin them. The foliage is not Bonny, but the other plants up there will disguise the mess they make as they die off. You can pull them out in mid summer when they've gone yellow without harming the bulbs, or just leave them to die back on their own...depends how tidy you want it!