Persian speedwell
Veronica persica
Plantaginaceae · [VERIFY] · naturalized
Last updated
Persian speedwell is a winter-annual weedy species native to Eurasia. It prefers partial to full sun, moist rich loamy soil, but adapts to poor soil. Most growth occurs during cool late-winter and early spring, blooming through early summer.
Persian speedwell is found in lawns, fields, gardens, and disturbed areas across much of North America. It reproduces entirely by seed and is notable for its ability to colonize poor and disturbed soils. It blooms early in the season before many perennials emerge.
Quick Facts
Phenological Calendar
As of April 19, 2026, Puget Sound stations range from 1342.9 to 1500.8 GDD₃₂. Persian speedwell has passed beginning of flowering (120 GDD₃₂).
Regional Season Tracker
GDD₃₂ accumulation across 7 Puget Sound stations · as of Apr 19, 2026| Station | GDD₃₂ | Current Stage | Next | To Go |
|---|---|---|---|---|
| Issaquah / East King | 1,501 | Beginning of flowering | — | — |
| Seattle / UW | 1,465 | Beginning of flowering | — | — |
| Kent / Auburn | 1,441 | Beginning of flowering | — | — |
| Olympia / Tumwater | 1,415 | Beginning of flowering | — | — |
| Bellingham / Whatcom | 1,390 | Beginning of flowering | — | — |
| Tacoma / Puyallup | 1,381 | Beginning of flowering | — | — |
| Sequim / Rain Shadow | 1,343 | Beginning of flowering | — | — |
| Stage | GDD32 | Typical Window |
|---|---|---|
| ● Beginning of flowering BBCH 61 NOW | 120 | — |
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 19, 2026. Predicted dates use 16-day weather forecast through May 5, 2026, then climate normals.