
Based on 2,245 research-grade iNaturalist observations in Colorado, Small White is most often recorded in July; in Colorado it behaves like a summer visitor / breeder. It ranks #6 among butterflies recorded in the state in our data.
Pieris rapae
Small White in Colorado 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 seen in Colorado in July

Weidemeyer's Admiral

Two-tailed Swallowtail

Taxiles Skipper

Rocky Mountain Parnassian

Monarch

Variegated Fritillary

Western Tiger Swallowtail

Painted Lady
Places to look in Colorado
White River National Forest
Denver Botanic Gardens
Rio Grande National Forest
National ForestSan Juan National Forest
Roxborough State Park
Mancos State Park
FAQ
When does Small White appear in Colorado?
Mainly April–September, with the most records in July.
How common is Small White in Colorado?
It ranks #6 by number of iNaturalist observations among butterflies in Colorado (2,245 records in our sample).