Spireas are divided into two main groups based on flowering.

 Spireas are divided into two main groups based on flowering time: spring-flowering and summer-flowering.

Spireas are divided into
two main groups
 based on flowering.

 Spring-flowering species: These shrubs bloom on the previous year's growth. Their flowers are usually white, gathered in umbels or corymbs, and bloom in May and June.

 Spiraea × cinerea 'Grefsheim' is a popular hybrid with graceful, arching shoots and double, snow-white flowers. Spiraea × vanhouttei is a large, spreading shrub with cascading branches covered in white flowers. Spiraea arguta is one of the earliest and most profusely blooming species with drooping branches. Spiraea nipponica is a dense shrub with dark green foliage and white inflorescences (the 'Snowmound' cultivar is well-known).

Spiraea Genus of shrubs.

 Spiraea (Latin: Spiraea) is a genus of deciduous ornamental shrubs in the rose family (Rosaceae), named for the beautifully curved branches, from the ancient Greek word "speira," meaning "spiral." 

 These are popular garden plants with abundant blooms, used to create hedges and landscapes. There are approximately 90 species of spirea, differing in bush shape, color, and flowering time.

Spiraea Genus of shrubs.

 Main characteristics of the genus

 Family: Rosaceae

 Type: Deciduous shrubs

 Distribution: Primarily Northern Hemisphere, temperate zone.

 Leaves: Simple, alternate, usually toothed or serrated.