Japanese Kerria Japanese Rose
Kerria japonica
Rosaceae · broadleaf deciduous shrub · introduced
Last updated
Data Coverage 5 of 6 dimensions
Quick Facts
Height
4–8 ft
Spread
6 ft
Growth Rate
Medium
Light
Part Shade
Soil
Moist
Water
Moderate
Hardiness
Zone Zones 4a–8b
Origin
central and western China, several cultivars available
Phenological Calendar
As of April 3, 2026, Puget Sound stations range from 1070 to 1180.6 GDD₃₂. Japanese Kerria Japanese Rose has reached 'first bloom' (1008 GDD₃₂) and is approaching 'full bloom', predicted around Apr 9.
Regional Season Tracker
GDD₃₂ accumulation across 7 Puget Sound stations · as of Apr 3, 2026| Station | GDD₃₂ | Current Stage | Next | To Go |
|---|---|---|---|---|
| Issaquah / East King | 1,181 | 'First bloom' | 'Full bloom' | 48 |
| Seattle / UW | 1,171 | 'First bloom' | 'Full bloom' | 58 |
| Kent / Auburn | 1,111 | 'First bloom' | 'Full bloom' | 118 |
| Olympia / Tumwater | 1,106 | 'First bloom' | 'Full bloom' | 123 |
| Bellingham / Whatcom | 1,101 | 'First bloom' | 'Full bloom' | 128 |
| Tacoma / Puyallup | 1,075 | 'First bloom' | 'Full bloom' | 154 |
| Sequim / Rain Shadow | 1,070 | 'First bloom' | 'Full bloom' | 159 |
| Stage | GDD32 | Typical Window |
|---|---|---|
| ● 'First bloom' BBCH '61' NOW | 1008 | '' |
| ○ 'Full bloom' BBCH '65' NEXT | 1229 | '' est. Apr 9 (forecast) |
Range: 768–918 GDD₃₂
(6yr)
GDD = Growing Degree Days (base 32°F, Jan 1 start). Why base 32? Hover over GDD values for source details. Season tracker for Kent / Auburn as of Apr 3, 2026. Predicted dates use 16-day weather forecast through Apr 19, 2026, then climate normals.
Diseases (11)
Raspberry bushy dwarf virus and related viruses Virus Thekopsora minima and Naohidemyces vaccinii Rust Podosphaera aphanis var. aphanis Powdery Mildew Peronospora sparsa Downy Mildew Rhizobium radiobacter (formerly Agrobacterium tumefaciens) Crown Gall Coniothyrium wernsdorffiae and Paraconiothyrium fuckelii Common canker Non-pathogenic (physiological — cold damage during flower... Bullhead Kalmusia coniothorium Brand canker Botrytis cinerea Botrytis Bud and Twig Blight [NOTE: Diplocarpon rosae causes black spot on roses (Rosa... Black Spot Chlaropsis thielavioides Black Mold
Pests (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