Japanese Spiraea 'Crispa'

Japanese spiraea 'Crispa' (Spiraea japonica 'Crispa') is a dwarf green cushion with curly foliage you recognise at a glance. The leaves are narrow, deeply and sharply toothed, twisted and crinkled. They open reddish-purple in spring and darken to glossy green through summer.

It is one of the lowest of all Japanese spiraeas: at ten years the bush is only about 0.5-1 m tall and as much across, which makes it ideal for edging, a low clipped ribbon or the front row of a mixed border. From May to July it is covered in deep pink flat corymbs up to 7 cm wide, though the real draw remains the texture of the leaves.

Key characteristics:

• What makes it special: The flat corymbs are a noticeable draw for butterflies, while the bush itself shrugs off town air and holds no interest for deer.
• Dimensions: At 10 years - 0.5-1 m tall and the same across.
• Hardiness: It withstands down to -34 °C (USDA zone 4).
• Flowering: From May to July deep pink flat corymbs up to 7 cm across open.
• Light: Best planted in full sun: it copes with light partial shade but flowers noticeably more modestly there.
• Soil: It takes any well-drained garden soil easily, and comes into its own on moist, rich loams.
• Watering: It likes even, moderate moisture - no drying out and no water standing at the roots.
• Care: It flowers on the current year's shoots, so prune in late winter or early spring; cutting off the spent corymbs brings a second wave.
• Landscape use: Low edgings and clipped bands, the front of a mixed border, and in mass it holds slopes against erosion beautifully.