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.
Quick Facts
Bloom Infection Window (Critical)
Primary Infection - Flowers and Young Leaves
Spring Canker Activation
Aecial Stage (Alternate Host)
+ 17 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. Bitter Cherry has passed 'first bloom' (1428 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 | 'First bloom' | — | — |
| Kent / Auburn | 2,089 | 'First bloom' | — | — |
| Seattle / UW | 2,063 | 'First bloom' | — | — |
| Olympia / Tumwater | 2,025 | 'First bloom' | — | — |
| Tacoma / Puyallup | 1,993 | 'First bloom' | — | — |
| Bellingham / Whatcom | 1,972 | 'First bloom' | — | — |
| Sequim / Rain Shadow | 1,906 | 'First bloom' | — | — |
| 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 May 13, 2026. Predicted dates use 16-day weather forecast through May 29, 2026, then climate normals.