Quick Guide: spring, hardy, full sun, height: 10cm/4in, width: 45-60cm/18 - 24in

It is easy to be dismissive of the ubiquitous Auhrieta deltoidea but it is in fact a very valuable plant, providing sweeps of dramatic colour on dry walls or in the rock garden in late spring, and lasting for weeks. The flowers are tiny but abundant, ranging in colour from lilac to deep purple. The plants form fast spreading mats.

GROWING Plant between autumn and spring in well-drained soil containing some lime. Plants grown on the rock garden should be sheared right back after flowering to keep them neat; if trailing over a wall, just snip off the old stems.

PROPAGATION Divide rooted stems of established plants in autumn and replant immediately.

VARIETIES 'Gurgedyke', old favourite, deep purple; `Dr Mules', reliable type, violet; `Bressingham Pink', double, rosypink; `Argenteo-Variegata', lavender flowers, leaves splashed silver.

POSSIBLE PROBLEMS White blister; downy mildew.