Great Willowherb
Epilobium hirsutum · Herbaceous Perennial (Note: The user submitted an herbaceous plant rather than a tree, but the botanical assessment is provided in this format)
Plant Family
Onagraceae
Tree Category
Wildflower / Herbaceous Perennial
Variety / Cultivar
Species type, no specific registered cultivar identified in the wild population
Hardiness Zones
USDA Hardiness Zones 4 to 9
About This Tree
An erect, robust perennial herb featuring hairy stems, densely-packed lanceolate leaves, and numerous showy pink to purplish-pink flowers followed by long, slender seed pods
Leaf Characteristics
Leaves are lance-shaped to oblong, hairy, sessile or clasping the stem, with finely toothed margins and a dark green color
Bark Characteristics
Not applicable to woody plants; stems are herbaceous, green to reddish-brown, and covered in soft hairs
Growing Information
Origin Region
Native to Europe, Asia, and parts of North Africa; widely naturalized in North America
Growing Season
Perennial growing season; emerges in spring, blooms profusely throughout summer (July to September), and dies back to rootstock in winter dormancy
Sunlight & Water Needs
Thrives in full sun to partial shade; requires moist to wet soils, commonly found near streams, ditches, and damp woodlands, with moderate drought intolerance once established
Mature Size
Typically reaches a height of 3 to 5 feet with a spread of 2 to 3 feet, growing at a fast rate
Special Characteristics
Highly adaptable to damp environments, vigorous spreader via rhizomes and abundant wind-borne seeds, attractive vibrant pink blooms
Wildlife & Ecology
Attracts numerous pollinators including bees, butterflies, and hoverflies; serves as a larval host plant for certain moth species