Centaurea nigra

Common knapweed is a tough, attractive, and easily grown hardy perennial flower, native to the British Isles. Nectar and pollen rich.  The seeds attract finches. Almost a weed. The pink-purple flowers lookalike mini thistles at first glance, (not prickly). Due to their hardiness they are perfect meadow plants and in spots that are hard to fill, Fine in sun or part shade, they flower over a long period, followed by architectural seed heads. 80-90cm high. open growth habit.  Supplied in Spring. Great for naturalising.