Spiraea is a member of the Rosaceae family and is a genus of around 80 to 100 species. It has narrow, oval leaves (lanceolate) which are usually toothed. The tiny white or pink flowers appear from late spring and through the summer and either form in densely-packed umbrella or grape-like clusters. They are a magnet for pollinating insects, especially butterflies.
Spiraea nipponica forms a dense, upright shrub approximately two metres high by two metres wide with blue-green leaves.
As the name suggests, it is native to Japan. The white flowers form on arching stems and is commonly called Spiraea Bridal Wreath, although this name seems to be used for various species including S. vanhouttei and S. X Arguta, the latter being one of the earliest in the genus to flower.
All species enjoy being in full sun although a little shade in the afternoon in the summer will prevent scorching. Spiraea is not fussy about soil, as long as it well drained, and will withstand some drought once established.
The flowers form on new growth so pruning should be carried out in late winter. Spiraea is fast growing and can be sheared after flowering to keep it tidy. It makes an ideal hedge or specimen plant for a cottage garden border or can be grown in a container.
Spiraea contains salicylic acid which is used in the preparation of aspirin and its curative properties were used as to treat inflammation by American native Indians. They also used it as an emetic and to treat venereal disease.