Spirea, a genus of about 100 species of deciduous shrubs. These plants are native to the temperate regions of the Northern Hemisphere. They usually reach a height of about four to six feet (1.2 to 1.8 m) and have lobed or tooth-edged leaves. Spireas are often cultivated as ornamentals for their profuse clusters of white, pink, or rose-colored flowers.
Spireas that bear white flowers in flattopped clusters, as in the species known as bridal wreath, bloom from April to June. Other species bloom from June until autumn. These have pyramid-shaped clusters of flowers either white or pale pink (as in the two species known as meadow-sweet) or rose-colored (as in the hardhack species).
Bridal wreath is Spiraea prunifolia; meadow-sweet, S. alba and S. latifolia; hardhack, S. tomentosa. All are of the rose family, Rosaceae.