meadowsweets (Spiraea) — identification, habitat & look-alikes

Spireas are a group of shrubs found in wetlands, open woods, and gardens, and most lose their leaves for part of the year. Their small leaves have a single blade, and their white, pink, or reddish flowers form rounded, flat-topped, or narrow clusters.

In this group

white meadowsweetSpiraea alba

A native shrub of wet meadows and stream edges in much of the northern and eastern United States; its white flowers form narrow upright clusters.

steeplebushSpiraea tomentosa

A native eastern shrub with pink to purplish, steeple-shaped clusters and woolly leaf undersides.

Douglas spireaSpiraea douglasii

A western native of wet meadows and streamside sites, recognized by dense pink flower plumes.

Japanese spireaSpiraea japonica

An Asian garden shrub that has escaped in parts of the eastern United States; look for flat-topped pink clusters on new growth.

Appearance

Growth form: Most form multi-stemmed shrubs, and some spread into colonies by root shoots.
Flowers: Flowers are usually white, pink, or reddish and appear in showy clusters.
Flowering time: In the United States, different species and cultivars bloom from spring into late summer, so the genus does not have one short bloom season.
Fruit: The fruit is a cluster of small dry that split to release seeds.
How to recognize it: These are usually with slender stems, alternate , and many tiny five-petaled flowers in rounded, flat-topped, or narrow clusters. Cluster shape, flower color, and leaf texture help separate the species.

Look-alikes

false spireasSorbaria

False spireas have made of many leaflets. Spiraea species generally have one simple leaf blade at each leaf stalk.

Why they get mixed upBoth are woody rose-family shrubs with masses of small white flowers.

astilbesAstilbe

Astilbes are nonwoody plants that die back to the ground and have divided, fernlike leaves. Spiraea keeps woody stems through winter and has simple leaves.

Why they get mixed upAstilbe is often sold under the common name false spirea.

meadowsweetsFilipendula

Meadowsweets have soft stems that die back after the growing season and divided leaves. Spiraea keeps woody stems and has simple leaves.

Why they get mixed upThe name meadowsweet is used for both groups.

Where it lives

Typical habitats: wet meadows and streambanks
open woods and rocky slopes
gardens and hedges
Range: The genus is native across much of the temperate Northern Hemisphere, including North America. The United States has native species such as white meadowsweet, steeplebush, and Douglas spirea, while several Asian species are grown or have escaped cultivation.
Preferred conditions: Needs vary by species. Native wetland spireas favor moist sites, while many garden spireas flower best in full sun and well-drained soil.

Growing it

Propagation: Garden plants can be propagated by seed, cuttings, or division, depending on the species.

Name and classification

About the name: Spireas are also called meadowsweets.
Group name: In U.S. gardens, these shrubs are usually called spireas. “Meadowsweet” also refers to the nonwoody meadowsweets (Filipendula).
Number of species: About 100 species are recognized worldwide.

Culture and stories

Culture and stories: Japanese spirea can form dense infestations in parts of the eastern United States, so check local invasive-plant guidance before planting it.

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