Spiraea nipponica Snowmound

Spiraea nipponica 'Snowmound', also known as Japanese Spiraea, is a very vigorous bush of medium size which is appreciated for its elegant and dense habit, its massive white garlands of flowers that bend its flexible branches towards the ground in early summer, and its ease of cultivation.

The 'Snowmound' Japanese Spiraea belongs to the Rosaceae family, native to China and Japan. The growth of this bush is fast, its adult size will easily reach 2m (6 ft 7in) in height, with a spread of 2.50m (8 ft 2in). The 'Snowmound' Japanese Spiraea has a dense, spreading, bushy and low habit. The very generous flowering takes place from May to June, and covers the bush with countless small white bouquets in flattened corymbs of 2 to 4cm (1.6in) consisting of small single flowers. They attract many insects and butterflies. The upright and erect branches carry arched twigs. The foliage is glossy, composed of small alternate, simple leaves, 1 to 3cm (1.2in) long, dark green on top and bluish underneath. Flowers and leaves appear on the same side of the arched branches. This spiraea takes on golden hues in autumn.

Plant Japanese Spiraea in any dry to moist, well-drained soil, preferably in full sun or partial shade. It will adapt to all climates and all soils but dislikes dense shade or hot and arid situations. Water well in the first year. This plant blooms on one-year-old branches. Consequently, pruning should be done sparingly, by removing one-third of the flowered branches every other year, just after flowering otherwise it will not flower the following spring. Light pruning promotes a small second flowering. Apply a general fertiliser in March. Plant with a spacing of 60cm (23.6in) to 1m (3ft 4in).

The 'Snowmound' Japanese Spiraea is mainly used as a standalone plant, in informal hedges, or in flower beds, in combination with trees and/or shrubs or to fill a large slope. Pair it with buddleias, 'Gloire de Versailles' Ceanothus, Diervilla splendens, Leycesteria formosa, or the large Styrax japonica.

The word Spiraea means "twisting" or "garland" in Greek; a legend says that the queen of the meadows used these flowers to make garlands. It was in the 16th century that the botanist Charles de l'Escluse attributed the name Spiraea to the entire genus. The nipponica species is native to Japan and the Japanese spiraea was recently introduced. It was discovered by the German naturalist Siebold in 1885 but was only introduced to Europe in 1908. It has been used to create several cultivars.