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Japanese spirea
Habit (mature) · AfroBrazilian / Wikimedia Commons · CC BY-SA 3.0
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Japanese spirea
Spiraea japonica
A dense, mounded deciduous shrub from Japan and China, grown for flat-topped corymbs of tiny pink flowers that cover the foliage from June into July above oval, sharply-toothed leaves. Easy and low-maintenance in full sun, it tolerates clay, deer, erosion, and urban conditions. It is also an aggressive self-seeder that has escaped gardens and naturalized across the eastern U.S., where several states list it as invasive.
Review: Source-backed
Climate fit: moderate (58/100)
Structure
Border
Pollinator
Light
Full sun / Part shade
Water
Moderate water
Mature size
48-72" tall · 60" apart
Hardy in zones
3a-8b
brutally cold to frosty winters
Summer heat range
Cool-Hot
cool to hot summers Interim Plotwright tier until the plant AHS range is authored.
Native in Illinois
No
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Transplanting and establishment
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Drainage and aeration
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Cold hardiness
Now
Zone 6b
USDA
Chicago, IL · 1991-2020 average annual coldest day
Source: USDA Plant Hardiness Zone Map 2023 (1991-2020 climatology) via ArcGIS FeatureServer
Well-suited
2050
Zone 7b
Plotwright
Your zone + climate-model shift · SSP3-7.0 (regional rivalry)
Well-suited
In plain terms: cold winters — coldest nights typically around -3°F.
Well-suited today and still thriving in 2050.
Heat tolerance
Loading current AHS heat-zone and plant heat-fit data at your coordinates…
Sources & citations
Cite this page
For lesson plans, articles, or research that uses this page. To cite a single upstream fact instead, use its specific source listed below.
Plotwright. (2026, May 17). Japanese spirea (Spiraea japonica). Retrieved 2026, June 5, from https://plotwright.garden/plants/japanese-spirea
Sources for every fact
Every fact on this page traces to a source. 18 fields cited18 source-backed.
Missouri Botanical Garden PlantFinder
Botanical research database
Backs 17 fields
Identity
Summary
Plant type
Light
Moisture
Hardiness
Heat zone
Size
Spacing
Habit
Design roles
Seasonal interest
Growth stages
Lifecycle
Regional guidance
Success tips
Designer notes
Wikimedia Commons
Photo · CC BY-SA 3.0
Backs 1 field
Image
NC State Extension Gardener Plant Toolbox
University extension service
Community photos
The photos above are our reviewed reference set, curated for accuracy.
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