Japanese Spiraea

Scientific Name: Spiraea japonica

Plant Family: Rosaceae

Native Region: East Asia (Japan, China, Korea) and widely naturalized in North America

Japanese Spiraea

Brief Description

A deciduous shrub known for its flat-topped clusters of tiny pink or rosy-red flowers and serrated, lance-shaped green leaves. It often has a dense, mounded growth habit.

Care Instructions

Low-maintenance. Provide full sun to partial shade in well-draining soil. Water regularly until established, and prune after flowering to maintain shape and encourage re-blooming.

Medicinal Value

We do not currently provide medicinal value for plant identifications.

Sunlight

Full sun to partial shade; prefers at least 6 hours of direct sunlight for best flowering.

Watering

Average water needs; water weekly or more often in extreme heat. Once established, it is moderately drought-tolerant.

Soil

Adaptable to various soil types including clay, but prefers moist, well-draining loamy soil with a neutral to slightly acidic pH (6.0-7.0).

Hardiness Zone

3 to 8

Growth Habit

Perennial shrub with a mounded, multi-stemmed growth habit. Typically reaches 4-6 feet in height and spread, though many cultivars are smaller.

Bloom Season

Late spring to mid-summer; produces flat-topped clusters (corymbs) of pink or white flowers.

Toxicity

Generally considered non-toxic to humans and common pets, though ingestion of any plant material may cause mild stomach upset.

Propagation

Easily propagated through softwood cuttings in summer or by seed in the autumn.

Common Pests & Issues

Susceptible to aphids, leaf spots, and powdery mildew. Can be invasive in certain natural woodland areas of the Eastern US.

Similar Species

Spiraea douglasii (Western Spiraea) which has steeple-shaped flower clusters, and Spiraea alba (Meadowsweet) which typically has white flowers.

Interesting Facts

The genus name 'Spiraea' comes from the Greek word 'speira', meaning wreath, referring to the flexible branches being suitable for weaving into garlands.

Created At: 2026-06-28T17:47:16.188993