Based on 1,383 research-grade iNaturalist flowering observations in Vermont, Painted Trillium blooms mainly from May to May, peaking in May. It ranks #6 among wildflowers recorded in the state in our data.
Trillium undulatum
Painted Trillium in Vermont by month
Bars show research-grade observations per month. They mix true seasonality with how often people are outdoors, so treat small numbers with caution.
Also in bloom in Vermont in May

Red Trillium

Jack-in-the-Pulpit

Large White Trillium

Yellow Trout Lily
Creeping Foamflower

Marsh Marigold
Carolina Springbeauty

Northern Starflower
Places to look in Vermont
State ParkElmore State Park
Quechee State Park
Wilgus State Park
Mount Philo State Park
Coolidge State Park
Crystal Lake State Park
FAQ
When does Painted Trillium bloom in Vermont?
Mainly May–May, with the most records in May.
How common is Painted Trillium in Vermont?
It ranks #6 by number of iNaturalist flowering observations among wildflowers in Vermont (1,383 records in our sample).