Culture
Easily grown in moist, fertile, well-drained soils in full sun. Tolerates light shade. Tolerates a wide range of soils. Remove faded flower clusters as practicable (light shearing is an option) to encourage additional bloom. Flowers appear on old wood, so prune each year as needed immediately after flowering.
Noteworthy Characteristics
Spiraea crenata, commonly called scalloped spirea, is a compact, small-leaved, multi-stemmed, deciduous, flowering shrub of the rose family featuring upright, spreading, reddish brown branches which typically grow to 2-4’ tall. It is native to stony, calcareous slopes and scrubs in eastern to northeastern Europe, the Balkan Peninsula, the Caucasus and northwestern Siberia. Lanceolate to obovate, acute, 3-veined, grayish-green leaves grow to 1 1/2” long on non-flowering branches, but smaller (narrower and shorter) on flowering branches. Leaves are typically entire, but sometimes finely toothed or scalloped. Leaves sometimes show attractive orange to red color in fall. Five-peraled white flowers (each to 1/4” across) bloom in April-May in dense, pubescent, almost stalkless, 10-20 flowered, domed umbels borne at the ends of small shoots. Flowers are attractive to butterflies. Flowers give way to follicles.
Genus name comes from the Greek word speira meaning wreath in reference to the showy flower clusters seen on most shrubs in the genus.
Specific epithet comes from the Greek word crenatus meaning scalloped in reference to leaf margins.
Problems
No serious insect or disease problems. Susceptible to many of the diseases and insects that attack other rose family members, including leaf spot, fireblight, powdery mildew, root rot, aphids, leaf roller and scale.
Uses
Mass or group in shrub borders. Low hedge for paths and walkways. Incorporates well into foundation plantings. Butterfly gardens.