Native perennial legume with blue to purple flowers, blooming May to September. Highly variable characteristics; occasionally rhizomatous. Prefers moist sites such as wetlands, damp forests, wet meadows and streambanks but also tolerant of seasonally dry sites; up to 11,000 ft. elevation. Versatile and competitive, able to grow in acidic, nutrient-poor mineral soils. Nectar and pollen-rich flowers attract beneficial insects, hummingbirds and numerous bees.