Geranium nodosum (Knotted cranesbill):
Fast spreading hardy geranium with purplish pink flowers over a long season in summer. A great gap filler. Up to 50cm.
Geranium palmatum:
Bright pink flowers held on wiry stems above rosettes of evergreen foliage. To 60cm. Frost hardy.
Stachys macrantha 'Rosea' (Betony 'Rosea'):
Upright spikes of pale pink flowers above pointed dark green foliage. The flowers are a bit orchid like in shape. Very attractive to bees. To 50cm. Hardy.