Red Flowering Horsechestnut
Aesculus carnea
Sapindaceae, Hippocastanaceae · broadleaf deciduous tree · introduced
Last updated
Data Maturity Baseline
This profile contains verified botanical data. Regional field notes and expert review are in progress.
Quick Facts
Height
35–50 ft
Light
Full Sun to Shade
Hardiness
Zone Zones 4–5
Phenological Calendar
As of April 29, 2026, Puget Sound stations range from 1558.2 to 1719 GDD₃₂. Red Flowering Horsechestnut has reached 'first bloom' (1368 GDD₃₂) and is approaching 'full bloom', predicted around Apr 30.
Regional Season Tracker
GDD₃₂ accumulation across 7 Puget Sound stations · as of Apr 29, 2026| Station | GDD₃₂ | Current Stage | Next | To Go |
|---|---|---|---|---|
| Issaquah / East King | 1,719 | 'Full bloom' | — | — |
| Seattle / UW | 1,676 | 'Full bloom' | — | — |
| Kent / Auburn | 1,670 | 'First bloom' | 'Full bloom' | 2 |
| Olympia / Tumwater | 1,626 | 'First bloom' | 'Full bloom' | 46 |
| Bellingham / Whatcom | 1,615 | 'First bloom' | 'Full bloom' | 57 |
| Tacoma / Puyallup | 1,595 | 'First bloom' | 'Full bloom' | 77 |
| Sequim / Rain Shadow | 1,558 | 'First bloom' | 'Full bloom' | 114 |
| Stage | GDD32 | Typical Window |
|---|---|---|
| ● 'First bloom' BBCH '61' NOW | 1368 | '' |
| ○ 'Full bloom' BBCH '65' NEXT | 1672 | '' est. Apr 30 (forecast) |
Source: 'Master catalog (OSU, UMD), GDD50 base' About GDD₃₂ →
Season tracker for Kent / Auburn as of Apr 29, 2026. Predicted dates use 16-day weather forecast through May 15, 2026, then climate normals.