Alchemilla mollis (Lady's mantle):
Bright green soft leaves and a froth of acid yellow/green flowers in summer. Very easy for ground cover. Height to 30cm.
Centaurea dealbata (Persian cornflower):
Large, showy pink flowers over deeply divided foliage. Makes a good-sized clump in a couple of years. To 60cm. Hardy.
[Collect Only]
Cephalaria gigantea (Giant scabious):
Very tall wavy stems topped with large lemon yellow scabious-like flowers. Easy to grow. May need staking or support. Hardy. Up to 2m.