Rose

'Leaf emergence'

Spiraea douglasii

Rosaceae · broadleaf deciduous shrub · native

Last updated

Douglas spirea, also called rose spirea, is a deciduous shrub native to moist habitats of western North America from British Columbia to California, reaching 3-6 feet tall. It produces narrow, hairy leaves and dense, rose-pink flower spikes appearing in mid- to late summer.

This species thrives in moist to wet soils in full sun to part shade and is hardy to zones 5-8. It spreads vigorously via rhizomes and self-seeding and is useful for wetland restoration, riparian plantings, and naturalized gardens. The plant requires consistent moisture and does not tolerate drought.

Quick Facts

Height
7 ft
Growth Rate
Moderate
Light
Full Sun
Soil
Adaptable
Water
Low
Hardiness
Zone Zones 4b–8b
Bloom Time
June to August
Origin
from Oregon to Alaska, found in marsh borders
Watch for this season

Primary Infection

Spring New Growth - Early Infection Window

RustHigh

Aecial Stage (Alternate Host)

Spring Emergence / Primary Infection

+ 4 more — see full disease and pest lists below

Phenological Calendar

As of May 13, 2026, Puget Sound stations range from 1906.2 to 2098.2 GDD₃₂. Rose has passed 'leaf emergence' (730 GDD₃₂).

Regional Season Tracker

GDD₃₂ accumulation across 7 Puget Sound stations · as of May 13, 2026
Station GDD₃₂ Current Stage Next To Go
Issaquah / East King 2,098 'Leaf emergence'
Kent / Auburn 2,089 'Leaf emergence'
Seattle / UW 2,063 'Leaf emergence'
Olympia / Tumwater 2,025 'Leaf emergence'
Tacoma / Puyallup 1,993 'Leaf emergence'
Bellingham / Whatcom 1,972 'Leaf emergence'
Sequim / Rain Shadow 1,906 'Leaf emergence'
Stage GDD32 Typical Window
'Bud break' BBCH '07' 730 ''
'Fall color / leaf senescence' BBCH '93' 730 ''
'Leaf emergence' BBCH '11' NOW 730 ''

Source: 'NPN citizen science observations (WA+OR), n=20, median. services.usanpn.org' About GDD₃₂ →

Season tracker for Kent / Auburn as of May 13, 2026. Predicted dates use 16-day weather forecast through May 29, 2026, then climate normals.

Diseases: Regionally Documented (11)

Pests: Regionally Documented (15)

Data Maturity
Structured Multiple sources. Expert review underway.