Height 15-20cm (6-8in)
Planting distance 15cm (6in)
Flowers mid and late spring
Rhizomes available in late and mid autumn
Convallaria majalis is the only species in this genus. It has delicate white bell-shaped, arranged in loose spikes. These appear in mid and late spring and have a magnificent heady scent that makes them popular as cut flowers. The berries that appear in autumn, and the roots, are poisonous.
Lily-of-the-valley is best planted in large clumps in a cool shady corner or in a wild garden; it spreads rapidly, so avoid confined spaces or borders where it can overcome more delicate plants. When you choose the site, bear in mind that the broad green leaves which provide such deceptively good ground cover in late spring and early summer become an untidy decaying yellow and brown mass towards the autumn. This problem is made worse if the plants are growing in a bright, sunny site.
Grow lily-of-the-valley in ordinary garden soil containing plenty of leaf-mould or compost. The site should be shady. Plant the crowns singly in early and mid autumn at least 15cm (6in) apart, pointed end upwards, and just below the soil surface. When the leaves die down in summer, top-dress with leaf-mould, compost or shredded forest bark – this encourages continuous flowering the following year. Avoid disturbing the roots except for propagation.
Lift and divide the rhizomes any time between mid autumn and early spring. Replant 15cm (6in) apart just below the surface, then apply a top-dressing of compost and leaf-mould and water well.
Pests and diseases
Swift moth caterpillars sometimes eat the rhizomes of established plants. In wet sites, a grey mould fungus can develop on the plants.