Piggyback Plant
Tolmiea menziesii
Saxifragaceae · perennial · native
Last updated
Piggyback plant is a native perennial of the Pacific Coast reaching 2 ft with a spreading growth form. It produces inconspicuous brown and green flowers and has characteristic young plantlets that form on the upper surface of mature leaves.
Piggyback plant is hardy in zones 7a-9b and requires full shade with moist soil and moderate moisture. It is low-maintenance and makes an excellent groundcover for shaded, moist areas. It tolerates some drought stress once established and spreads via the plantlets that readily root in soil.
Quick Facts
Phenological Calendar
As of April 3, 2026, Puget Sound stations range from 1070 to 1180.6 GDD₃₂. Piggyback Plant typically reaches 'flower buds visible' at 1276 GDD₃₂, predicted around Apr 11.
Regional Season Tracker
GDD₃₂ accumulation across 7 Puget Sound stations · as of Apr 3, 2026| Station | GDD₃₂ | Current Stage | Next | To Go |
|---|---|---|---|---|
| Issaquah / East King | 1,181 | Pre-season | 'Flower buds visible' | 95 |
| Seattle / UW | 1,171 | Pre-season | 'Flower buds visible' | 105 |
| Kent / Auburn | 1,111 | Pre-season | 'Flower buds visible' | 165 |
| Olympia / Tumwater | 1,106 | Pre-season | 'Flower buds visible' | 170 |
| Bellingham / Whatcom | 1,101 | Pre-season | 'Flower buds visible' | 175 |
| Tacoma / Puyallup | 1,075 | Pre-season | 'Flower buds visible' | 201 |
| Sequim / Rain Shadow | 1,070 | Pre-season | 'Flower buds visible' | 206 |
| Stage | GDD32 | Typical Window |
|---|---|---|
| ○ 'Flower buds visible' BBCH '51' NEXT | 1276 | '' est. Apr 11 (forecast) |
GDD = Growing Degree Days (base 32°F, Jan 1 start). Why base 32? GDD₃₂ thresholds from USA National Phenology Network citizen science observations (WA+OR). Season tracker for Kent / Auburn as of Apr 3, 2026. Predicted dates use 16-day weather forecast through Apr 19, 2026, then climate normals.