Persian Lilac
Syringa persica
Oleaceae · broadleaf deciduous shrub · introduced
Last updated
Data Maturity Baseline
This profile contains verified botanical data. Regional field notes and expert review are in progress.
Quick Facts
Height
4–8 ft
Growth Rate
Medium
Light
Full Sun to Part Shade
Soil
Well Drained
Water
Moderate
Hardiness
Zone Zones 5a–8b
Fall Color
Insignificant
Phenological Calendar
As of April 29, 2026, Puget Sound stations range from 1558.2 to 1719 GDD₃₂. Persian Lilac has passed 'full bloom' (1364 GDD₃₂).
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 | 'Full bloom' | — | — |
| Olympia / Tumwater | 1,626 | 'Full bloom' | — | — |
| Bellingham / Whatcom | 1,615 | 'Full bloom' | — | — |
| Tacoma / Puyallup | 1,595 | 'Full bloom' | — | — |
| Sequim / Rain Shadow | 1,558 | 'Full bloom' | — | — |
| Stage | GDD32 | Typical Window |
|---|---|---|
| 'First bloom' BBCH '61' | 1080 | '' |
| ● 'Full bloom' BBCH '65' NOW | 1364 | '' |
Source: 'Master catalog (OSU), 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.