Japanese Kerria Japanese Rose
'Full bloom'Kerria japonica
Rosaceae · broadleaf deciduous shrub · introduced
Last updated
Quick Facts
Height
4–8 ft
Spread
6 ft
Growth Rate
Medium
Light
Part Shade
Soil
Moist
Water
Moderate
Hardiness
Zone Zones 4a–8b
Fall Color
Yellow
Origin
central and western China, several cultivars available
Watch for this season
Black SpotHigh
Primary Infection
Downy MildewHigh
Spring New Growth - Early Infection Window
RustHigh
Aecial Stage (Alternate Host)
Powdery MildewModerate
Spring Emergence / Primary Infection
+ 3 more — see full disease and pest lists below
Phenological Calendar
As of May 14, 2026, Puget Sound stations range from 1926.1 to 2121.1 GDD₃₂. Japanese Kerria Japanese Rose has passed 'full bloom' (1229 GDD₃₂).
Regional Season Tracker
GDD₃₂ accumulation across 7 Puget Sound stations · as of May 14, 2026| Station | GDD₃₂ | Current Stage | Next | To Go |
|---|---|---|---|---|
| Issaquah / East King | 2,121 | 'Full bloom' | — | — |
| Kent / Auburn | 2,113 | 'Full bloom' | — | — |
| Seattle / UW | 2,085 | 'Full bloom' | — | — |
| Olympia / Tumwater | 2,047 | 'Full bloom' | — | — |
| Tacoma / Puyallup | 2,016 | 'Full bloom' | — | — |
| Bellingham / Whatcom | 1,994 | 'Full bloom' | — | — |
| Sequim / Rain Shadow | 1,926 | 'Full bloom' | — | — |
| Stage | GDD32 | Typical Window |
|---|---|---|
| 'First bloom' BBCH '61' | 1008 | '' |
| ● 'Full bloom' BBCH '65' NOW | 1229 | '' |
Range: 768–918 GDD₃₂
(6yr)
Source: 'Master catalog (OSU), converted GDD50->GDD32 via Kent bloom-date mapping' About GDD₃₂ →
Season tracker for Kent / Auburn as of May 14, 2026. Predicted dates use 16-day weather forecast through May 30, 2026, then climate normals.
Diseases: Regionally Documented (10)
Raspberry bushy dwarf virus and related viruses Virus Multiple genera (Melampsoridium, Thekopsora, Naohidemyces... Rust Multiple obligate biotrophic fungi (Erysiphales: Erysipha... Powdery Mildew Multiple obligate oomycetes (Peronosporaceae); species ar... Downy Mildew Rhizobium radiobacter (formerly Agrobacterium tumefaciens) Crown Gall Coniothyrium wernsdorffiae and Paraconiothyrium fuckelii Common canker Kalmusia coniothorium Brand canker Botrytis Bud and Twig Blight [NOTE: Diplocarpon rosae causes black spot on roses (Rosa... Black Spot Chlaropsis thielavioides Black Mold
Pests: Regionally Documented (13)
Diabrotica undecimpunctata Western spotted cucumber beetle Chloridea virescens Tobacco budworm Thysanoptera Thrips Tetranychidae Spider mite Endelomyia aethiops Roseslug Dasineura rhodophaga Rose midge Edwardsiana rosae Rose leafhopper Diplolepis rosae Rose galls Macrosiphum rosae Rose aphid Otiorhynchus spp. Root weevil Schizura concinna Redhumped caterpillar Tortricidae Leafroller Megachile spp. Leafcutting bee
Cultivars (5)
'Albiflora'
Common name: White Japanese Kerria, Albiflora Japanese Kerria; Mature height: 4–5 ft
Hardy to USDA Zone 4
'Golden Guinea'
Common name: Golden Guinea Japanese Kerria; Mature height: 4–5 ft
Hardy to USDA Zone 4
'Kin Kan'
Common name: Kin Kan Japanese Kerria
Hardy to USDA Zone 4
'Picta'
Common name: Variegated Japanese Kerria, Picta Japanese Kerria; Mature height: 3–4 ft
Hardy to USDA Zone 4
'Pleniflora'
Common name: Double Japanese Kerria; Mature height: 4–8 ft
Hardy to USDA Zone 4
Data Maturity Structured Multiple sources. Expert review underway.