Crimsoneyed rosemallow
Hibiscus moscheutos
Malvaceae · [VERIFY] · native
Last updated
Vigorous, shrubby, woody-based perennial to 3 to 7 feet with showy, dinner plate-sized hollyhock-like flowers (4 to 6 inches diameter) in white, pink, or cream with reddish-purple to dark crimson centers.
Rapid growth requires full sun and moist, organically rich soils; deep watering is essential during establishment. Tolerates heat and humidity; suited to moist borders, wet areas, stream and pond margins, and large containers.
Quick Facts
Phenological Calendar
As of April 19, 2026, Puget Sound stations range from 1342.9 to 1500.8 GDD₃₂. Crimsoneyed rosemallow typically reaches beginning of flowering at 6899 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 | Pre-season | Beginning of flowering | 5,398 |
| Seattle / UW | 1,465 | Pre-season | Beginning of flowering | 5,434 |
| Kent / Auburn | 1,441 | Pre-season | Beginning of flowering | 5,458 |
| Olympia / Tumwater | 1,415 | Pre-season | Beginning of flowering | 5,484 |
| Bellingham / Whatcom | 1,390 | Pre-season | Beginning of flowering | 5,509 |
| Tacoma / Puyallup | 1,381 | Pre-season | Beginning of flowering | 5,519 |
| Sequim / Rain Shadow | 1,343 | Pre-season | Beginning of flowering | 5,556 |
| Stage | GDD32 | Typical Window |
|---|---|---|
| ○ Beginning of flowering BBCH 61 NEXT | 6899 | — |
| Full bloom BBCH 65 | 7571 | — |
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.