Quince
Cydonia oblonga
Rosaceae · broadleaf deciduous tree · introduced
Last updated
Data Maturity Structured
This profile synthesizes data from multiple published sources. Expert field review is in progress.
Quick Facts
Height
15 ft
Spread
23 ft
Growth Rate
Slow
Light
Full Sun
Soil
Well Drained
Water
Moderate
Hardiness
Zone Zones 5a–8b
Bloom Time
April to May
Origin
Iran and Turkestan
Phenological Calendar
As of April 23, 2026, Puget Sound stations range from 1434.4 to 1592.7 GDD₃₂. Quince has passed 'flower buds visible' (1072 GDD₃₂).
Regional Season Tracker
GDD₃₂ accumulation across 7 Puget Sound stations · as of Apr 23, 2026| Station | GDD₃₂ | Current Stage | Next | To Go |
|---|---|---|---|---|
| Issaquah / East King | 1,593 | 'Flower buds visible' | — | — |
| Seattle / UW | 1,554 | 'Flower buds visible' | — | — |
| Kent / Auburn | 1,537 | 'Flower buds visible' | — | — |
| Olympia / Tumwater | 1,505 | 'Flower buds visible' | — | — |
| Bellingham / Whatcom | 1,483 | 'Flower buds visible' | — | — |
| Tacoma / Puyallup | 1,472 | 'Flower buds visible' | — | — |
| Sequim / Rain Shadow | 1,434 | 'Flower buds visible' | — | — |
| Stage | GDD32 | Typical Window |
|---|---|---|
| 'Bud break' BBCH '07' | 912 | '' |
| 'Leaf emergence' BBCH '11' | 912 | '' |
| ● 'Flower buds visible' BBCH '51' NOW | 1072 | '' |
GDD = Growing Degree Days (base 32°F, Jan 1 start). Why base 32? GDD₃₂ thresholds from USA National Phenology Network citizen science observations (WA+OR). Season tracker for Kent / Auburn as of Apr 23, 2026. Predicted dates use 16-day weather forecast through May 9, 2026, then climate normals.