Epilobium glaberrimum, commonly known as glaucous willowherb, is a perennial herb native to a variety of moist habitats in western North America, from central Canada to northern Mexico, including mountain meadows, wetland margins, and streambanks. It typically grows to a height of over half a meter, with smooth, hairless foliage and lance-shaped leaves that are 0-3 inches long. The plant produces showy flowers with four notched petals that can be purple, pink, or white, blooming from late spring to early fall. The fruit is a slender capsule 1-3 inches long, which releases numerous seeds with tufts of hair that aid in wind dispersal.

Glaucous willowherb is valued for its nectar-rich flowers that attract pollinators such as bees and butterflies, contributing to the biodiversity of its native habitats. It is used in wildflower gardens, naturalized areas, and for revegetation projects, especially in moist or riparian settings. This species prefers moist, well-drained soils and can tolerate a range of light conditions from full sun to partial shade. While generally low-maintenance, it can spread aggressively by rhizomes and self-seeding, which may require management in garden settings.CC BY-SA 4.0