Allium sphaerocephalon

Also known as the round headed leek, Allium sphaerocephalon in a very useful plant which can fill gaps in a border and will grow up in between other plants. It is very attractive to bees of various colours and hoverflies. The extra shows a clump of them. It is also cheap. It is featured on the front cover of the book "Dream Plants for the natural garden" by Piet Oudolf and Henk Gerritsen, which advises buying a large sackful!