Adirondack Crabapple
Malus 'Adirondack'
Rosaceae · broadleaf deciduous tree · introduced
Last updated
Malus 'Adirondack' (Rosaceae) is a deciduous ornamental crabapple cultivar noted for its narrow, upright habit and heavy spring bloom. White flowers open from red buds, and small persistent fruit provides winter interest and wildlife food.
This cultivar performs in full sun on well-drained soil. Bloom begins around 260 GDD (base 50 F) with full bloom near 379 GDD. Disease resistance is a key selection trait in modern crabapple breeding. Like all Malus, it benefits from good air circulation to reduce foliar disease pressure.
Quick Facts
Phenological Calendar
As of April 12, 2026, Puget Sound stations range from 1235.8 to 1375.3 GDD₃₂. Adirondack Crabapple has reached beginning of flowering (1170 GDD₃₂) and is approaching full bloom, predicted around May 3.
Regional Season Tracker
GDD₃₂ accumulation across 7 Puget Sound stations · as of Apr 12, 2026| Station | GDD₃₂ | Current Stage | Next | To Go |
|---|---|---|---|---|
| Issaquah / East King | 1,375 | Beginning of flowering | Full bloom | 331 |
| Seattle / UW | 1,348 | Beginning of flowering | Full bloom | 358 |
| Kent / Auburn | 1,308 | Beginning of flowering | Full bloom | 398 |
| Olympia / Tumwater | 1,292 | Beginning of flowering | Full bloom | 414 |
| Bellingham / Whatcom | 1,270 | Beginning of flowering | Full bloom | 436 |
| Tacoma / Puyallup | 1,258 | Beginning of flowering | Full bloom | 448 |
| Sequim / Rain Shadow | 1,236 | Beginning of flowering | Full bloom | 470 |
| Stage | GDD32 | Typical Window |
|---|---|---|
| ● Beginning of flowering BBCH 61 NOW | 1170 | — |
| ○ Full bloom BBCH 65 NEXT | 1706 | — est. May 3 (avg) |
GDD = Growing Degree Days (base 32°F, Jan 1 start). Why base 32? Source GDD₅₀ thresholds from Herms 2004 (OSU, Secrest Arboretum, Ohio) and UMD IPMnet (Gill & Klick, mid-Atlantic), converted to GDD₃₂ via Kent bloom-date mapping. Season tracker for Kent / Auburn as of Apr 12, 2026. Predicted dates use 16-day weather forecast through Apr 28, 2026, then climate normals.