When planting, avoid planting too deeply, and incorporate well-rotted compost or manure into the planting hole, adding some mycorrhizal fungi to aid root establishment.

Remove spent flower spikes regularly to encourage prolonged flowering. In late autumn, after flowering has finished, cut back any dead or damaged growth to maintain a tidy shape. In early spring, prune lightly to remove any winter-damaged stems and to promote strong, healthy new growth.

Apply a generous 5-7cm (2-3in) mulch of leaf mould around the base of the plant each spring. Protect from strong winter winds.