Spiraea Arguta or Garland Spiraea
The generic name is derived from the Greek word speira, but opinions differ as to its proper meaning. The genus contains some 80 species distributed throughout the temperate regions of the northern hemisphere. In Asia their range extends as far as the Himalayas, in North America to Mexico. Only a few species are found in Europe. Spiraeas are shrubs growing to a height of 0.5 to 4m (1½ to 13 ft). The leaves are alternate, simple, toothed or serrate, less often entire, with short petioles. Theare borne in short umbel-like clusters, have five sepals, five petals and 15 to 60 stamens. The fruits are follicles that split when ripe.
Spiraeas are distinguished by the extensive period of flowering represented by the various species. Some flower in early spring, often before the leaves open, others not until June, continuing until September. Spiraea arguta, a hybrid between Spiraea thunbergii and Spiraea multiflora, is an early-flowering form. It is a thickly branched shrub with fine, slender shoots, growing to a height of 2m (6 ft) and bearing a profusion of snow-white flowers in late April and early May.
Spiraeas will grow almost anywhere, even in poor and dry. They thrive in sunny locations but tolerate slight shade.