Bitter Cherry
'First bloom'Prunus emarginata
Rosaceae · broadleaf deciduous shrub · native
Last updated
Prunus emarginata (Rosaceae) is a deciduous tree or large shrub native to western North America from British Columbia to California. It grows 20 to 40 feet tall, often forming thickets via root suckers. Small white flowers appear in flat-topped clusters in spring, followed by small, bitter, bright red cherries.
Bitter cherry grows in sun to part shade on moist to dry, well-drained soils. The fruit is extremely bitter and inedible raw but was used by indigenous peoples after processing. It is valued in restoration plantings for its wildlife food value (birds and bears consume the fruit) and ability to colonize disturbed sites. Hardy in Zones 6a to 8b.
Plant Profile
Size & Form
Site Requirements
Ornamental Interest
Primary Infection - Flowers and Young Leaves
Peak Spore Production and Dispersal
Active Conidial Spread
Uredinial Stage (Summer)
+ 17 more — see full disease and pest lists below
Diseases: Regionally Documented (51)
Pests: Regionally Documented (31)
Phenological Calendar
As of June 3, 2026, Puget Sound stations range from 2435.5 to 2672.8 GDD₃₂. Bitter Cherry has passed 'first bloom' (1428 GDD₃₂).
Regional Season Tracker
GDD₃₂ accumulation across 7 Puget Sound stations · as of Jun 3, 2026| Station | GDD₃₂ | Current Stage | Next | To Go |
|---|---|---|---|---|
| Issaquah / East King | 2,673 | 'First bloom' | — | — |
| Kent / Auburn | 2,665 | 'First bloom' | — | — |
| Seattle / UW | 2,610 | 'First bloom' | — | — |
| Olympia / Tumwater | 2,570 | 'First bloom' | — | — |
| Tacoma / Puyallup | 2,535 | 'First bloom' | — | — |
| Bellingham / Whatcom | 2,533 | 'First bloom' | — | — |
| Sequim / Rain Shadow | 2,436 | 'First bloom' | — | — |
View full calendar (4 stages)
| Stage | GDD32 | Typical Window |
|---|---|---|
| 'Bud break' BBCH '07' | 1144 | '' |
| 'Flower buds visible' BBCH '51' | 1252 | '' |
| 'Leaf emergence' BBCH '11' | 1276 | '' |
| ● 'First bloom' BBCH '61' NOW | 1428 | '' |
Source: 'NPN citizen science observations (WA+OR), n=11, median. services.usanpn.org' About GDD₃₂ →
Season tracker for Kent / Auburn as of Jun 3, 2026. Predicted dates use 16-day weather forecast through Jun 19, 2026, then climate normals.