Daylily
Hemerocallis
Asphodelaceae · perennial · introduced
Last updated
Daylily (Hemerocallis, Asphodelaceae) is a genus of perennials, each flower lasting just one day (the genus name derives from the Greek hemera, day, and kallos, beauty). Over 80,000 cultivars have been registered. Bloom periods span spring through frost depending on cultivar selection.
Documented diseases include daylily rust; pest associations include thrips and daylily gall midge. Daylily petals are edible in many cultivars but the plant is toxic to cats (potentially fatal). See Hemerocallis hybrid for cultivar details.
Plant Profile
Size & Form
Site Requirements
Field Observations
Diseases: Regionally Documented (1)
Pests: Regionally Documented (2)
Phenological Calendar
As of June 3, 2026, Puget Sound stations range from 2435.5 to 2672.8 GDD₃₂. Daylily typically reaches 'full bloom' at 3398 GDD₃₂, predicted around Jun 30.
Regional Season Tracker
GDD₃₂ accumulation across 7 Puget Sound stations · as of Jun 3, 2026| Station | GDD₃₂ | Current Stage | Next | To Go |
|---|---|---|---|---|
| Issaquah / East King | 2,673 | Pre-season | 'Full bloom' | 725 |
| Kent / Auburn | 2,665 | Pre-season | 'Full bloom' | 733 |
| Seattle / UW | 2,610 | Pre-season | 'Full bloom' | 788 |
| Olympia / Tumwater | 2,570 | Pre-season | 'Full bloom' | 829 |
| Tacoma / Puyallup | 2,535 | Pre-season | 'Full bloom' | 863 |
| Bellingham / Whatcom | 2,533 | Pre-season | 'Full bloom' | 865 |
| Sequim / Rain Shadow | 2,436 | Pre-season | 'Full bloom' | 963 |
View full calendar (1 stages)
| Stage | GDD32 | Typical Window |
|---|---|---|
| ○ 'Full bloom' BBCH '65' NEXT | 3398 Observed | '' est. Jun 30 (avg) |
Source: Field observation, Kent, WA (Purple D'Oro), n=1 About GDD₃₂ →
Season tracker for Kent / Auburn as of Jun 3, 2026. Predicted dates use 16-day weather forecast through Jun 19, 2026, then climate normals.