Syringa pubescens
Syringa pubescens
· deciduous shrub · introduced
Last updated
Syringa pubescens is a deciduous shrub native to northern China, reaching 6-12 feet tall with small, narrow leaves and panicles of fragrant, pale pink to lilac flowers appearing in late spring. The plant is more refined and less coarse than common lilac.
This species is hardy to zones 3-7 and thrives in full sun to light shade with well-drained soil. It is less susceptible to mildew and scale than common lilac and requires minimal maintenance. The late bloom time extends the lilac season in the garden.
Phenological Calendar
Regional Season Tracker
GDD₃₂ accumulation across 7 Puget Sound stations · as of Mar 22, 2026| Station | GDD₃₂ | Current Stage | Next | To Go |
|---|---|---|---|---|
| Seattle / UW | 1,013 | Pre-season | Beginning of flowering | 591 |
| Issaquah / East King | 1,006 | Pre-season | Beginning of flowering | 598 |
| Olympia / Tumwater | 952 | Pre-season | Beginning of flowering | 652 |
| Bellingham / Whatcom | 948 | Pre-season | Beginning of flowering | 656 |
| Kent / Auburn | 942 | Pre-season | Beginning of flowering | 662 |
| Sequim / Rain Shadow | 924 | Pre-season | Beginning of flowering | 680 |
| Tacoma / Puyallup | 921 | Pre-season | Beginning of flowering | 683 |
| Stage | GDD32 | Typical Window |
|---|---|---|
| ○ Beginning of flowering BBCH 61 NEXT | 1604 | — est. May 1 (avg) |
| Full bloom BBCH 65 | 1892 | — est. May 14 (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 Mar 22, 2026. Predicted dates use 16-day weather forecast through Apr 7, 2026, then climate normals.