Quick Guide: summer, hardy, sun/ Semi-shade, height: 12.5cm/5in, width: 45cm/18in

The large group of true geraniums or cranesbills includes severa1 species indispensable to the rock garden. Flowers may be pink, lilac or white and the attractive leaves form dense ground cover.

GROWING Plant in autumn or spring in well-drained soil in sun or partial shade. After flowering, cut back stems to ground level to keep the shape neat and encourage a second flush of flowers.

PROPAGATION Lift, divide and replant between autumn and spring.

SPECIES G. dalrnaticum forms cushions of foliage flushed orange in the autumn, pale pink flowers; G. x `Ballerina', strong-growing hybrid, grey-green leaves, pink flowers veined red; G. napuligerum, slow-growing, suitable for a rocky bank, pink flowers - `Album' is a white variety; G. pylzowianum, best ground cover plant for rock gardens, 7.5cm/3in high, relatively few pink flowers; G. renardii, clump-forming, with large lavender flowers veined purple; G. subcaulescens, bright crimson flowers in profusion from spring to autumn-the hybrid `Russell Prichard' makes excellent ground cover with grey-green leaves and large, rich pink flowers.

POSSIBLE PROBLEMS Slugs eat young plants; rust on leaves.