What will grow on a wall?
Q Purple toadflaxis growing in poor, rubbly soil along the base ofan old garden wall. Are there other toadflax varieties or anything else I could growwith them?
R Dawson, Northampton
ALinaria purpurea (toadflax) produces spires of tiny purple or pink snapdragon flowers all summer. It’s a vigorous, free-seeding perennial and thin, dry, free-draining
ground suits it best.
Other species include gorgeous perennial L. triornithophora with curiously spurred, larger flowers in pink, mauve or yellow; tallish, yellow-flowered L. dalmatica, and much smaller, weedier L. alpina. Both these plants seed freely. Other lovely plants for naturalising in old, crumbly walls include red valerian Centranthus rubier, ivy-leaved toadflax Cymbalaria muralis, and smaller sedums.
Plants to try
Pretty purple and orange flowers are produced in a sunny spot in summer.
Grown in full sun, red valerian flowers bloom from late spring to autumn.
Ivy-leaved toadflax prefers shade and forms mats of dainty purple flowers.
All photos Shutterstock
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