Very easily cultivated and a useful edging or border plant. Sow seeds in March in moist, loamy soil, in a partially shaded position. Increase by division of the crowns in spring. Some of the best species and varieties are:
B. perennis (Dresden China). Small double flowers of bright pink, from May to September. A charming subject for the cracks of paving.
B. perennis (Rob Roy). Bright crimson.
B. prolifera (Hen and Chickens). White and rose.
B. rotundifolia cceridescens. Lavendor-blue.