Hollow Joe pye weed
Eutrochium fistulosum
Asteraceae · [VERIFY] · native
Last updated
Tall, erect perennial to 4 to 7 feet with coarsely serrated, lance-shaped leaves arranged in whorls on sturdy, hollow green stems. Tiny vanilla-scented, dull pinkish-purple flowers appear in large, domed, compound inflorescences in mid-summer.
Prefers moist, fertile, humus-rich soils in full sun to part shade; tolerates average soils if moisture is consistent. Butterfly and pollinator magnet; dramatic architectural presence for back borders, cottage gardens, meadows, and water margins.
Quick Facts
Phenological Calendar
As of April 19, 2026, Puget Sound stations range from 1342.9 to 1500.8 GDD₃₂. Hollow Joe pye weed typically reaches beginning of flowering at 6983 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 | 5,482 |
| Seattle / UW | 1,465 | Pre-season | Beginning of flowering | 5,518 |
| Kent / Auburn | 1,441 | Pre-season | Beginning of flowering | 5,542 |
| Olympia / Tumwater | 1,415 | Pre-season | Beginning of flowering | 5,568 |
| Bellingham / Whatcom | 1,390 | Pre-season | Beginning of flowering | 5,593 |
| Tacoma / Puyallup | 1,381 | Pre-season | Beginning of flowering | 5,603 |
| Sequim / Rain Shadow | 1,343 | Pre-season | Beginning of flowering | 5,640 |
| Stage | GDD32 | Typical Window |
|---|---|---|
| ○ Beginning of flowering BBCH 61 NEXT | 6983 | — |
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.