Red Horsechestnut
Full bloomAesculus x carnea
Sapindaceae · [VERIFY] · introduced
Last updated
Hybrid horsechestnut reaching 35 to 50 feet tall with glossy, palmately compound foliage and showy pink to red flower spikes that appear in mid to late spring. Distinctive large candles of blossoms precede round, warty brown fruit.
Moderate maintenance ornamental shade tree preferring full sun and well-drained soil. Susceptible to Japanese beetle and scale insects. Excellent specimen tree for large landscapes; early leaf scorch can occur in hot, dry seasons.
Quick Facts
Phenological Calendar
As of May 15, 2026, Puget Sound stations range from 1942.5 to 2137.2 GDD₃₂. Red Horsechestnut has passed full bloom (1809 GDD₃₂).
Regional Season Tracker
GDD₃₂ accumulation across 7 Puget Sound stations · as of May 15, 2026| Station | GDD₃₂ | Current Stage | Next | To Go |
|---|---|---|---|---|
| Issaquah / East King | 2,137 | Full bloom | — | — |
| Kent / Auburn | 2,130 | Full bloom | — | — |
| Seattle / UW | 2,102 | Full bloom | — | — |
| Olympia / Tumwater | 2,064 | Full bloom | — | — |
| Tacoma / Puyallup | 2,033 | Full bloom | — | — |
| Bellingham / Whatcom | 2,012 | Full bloom | — | — |
| Sequim / Rain Shadow | 1,943 | Full bloom | — | — |
| Stage | GDD32 | Typical Window |
|---|---|---|
| Beginning of flowering BBCH 61 | 1562 | — |
| ● Full bloom BBCH 65 NOW | 1809 | — |
Source: UMD: extension.umd.edu) About GDD₃₂ →
Season tracker for Kent / Auburn as of May 15, 2026. Predicted dates use 16-day weather forecast through May 31, 2026, then climate normals.