Thalictrum dasycarpum
purple meadow-rue
Overview
Thalictrum dasycarpum is a clump-forming herbaceous perennial reaching 3-6 feet (0.9-1.8 m) tall, with erect stems often flushed purple. The leaves are divided two to three times into rounded, three-lobed leaflets 0.5-1.5 inches (1-4 cm) long, dull green above and paler beneath. It is dioecious, with male and female flowers on separate plants. The flowers lack petals; male flowers hang in airy clusters of pale greenish-white sepals and stamens with thread-like white to purplish filaments, while female flowers carry tufts of pistils that ripen into dry, ribbed achenes. Flowering occurs from June to July in open panicles held above the foliage. The species grows in moist prairies, wet meadows, streambanks, and thickets across central and eastern North America. Pollination is largely by wind, aided by some insect visitation to the stamens. Plants spread slowly from short rhizomes and self-sown seed, forming standing colonies over time. One limitation is the height of the flowering stems, which can lean or topple in exposed, windy sites without support from surrounding vegetation.
Native Range
Thalictrum dasycarpum is native to central and eastern North America, from the Prairie Provinces of Canada south through the Great Plains and Midwest to Texas, and east toward the Appalachian region. It is most frequent in tallgrass prairie and wet meadow habitats.Suggested Uses
Grown in rain gardens, pond and stream margins, native plant borders, and naturalised meadow plantings. The height suits the back of a border or a moist wildflower planting, spaced 18-24 inches (45-60 cm) apart. The early-summer flowers draw small bees and other insects to the stamens.How to Identify
Appearance
Size & Dimensions
Height3' - 6'
Width/Spread1' - 2'
Reaches mature size in approximately 3 years
Bloom Information
Flowers appear from June to July, held in branching panicles above the foliage. Male and female flowers occur on separate plants, so seed forms only where both are present. The pale stamens of male plants are most conspicuous in early summer.
Detailed Descriptions
Flower Description
greenish-white to purplishFoliage Description
greenGrowing Conditions
Sun Requirements
Requires 4-8 hours of direct sunlight daily
• Full Sun: 6+ hours of direct sunlight
• Partial Shade: 3-6 hours of direct sunlight
• Full Shade: Less than 3 hours of direct sunlight
Care & Maintenance
Care Guide
Thalictrum dasycarpum grows in full sun to part shade and consistently moist to wet soils rich in organic matter. It establishes from seed sown in autumn for cold stratification, or from division of dormant clumps in spring. Plants tolerate heavy clay and seasonal flooding but decline in dry, sandy soils. Once established, the rhizomes form expanding clumps that need little attention. Tall stems in open sites may lean and lean on neighbouring plants for support. Spent stems are cut to the ground after frost to keep the planting tidy through winter.Pruning
Spent flowering stems are cut back to the base after seed set or after the first hard frost. No other pruning is needed. Removing seed heads before they ripen limits self-sowing where spread is not wanted.Pruning Schedule
J
F
M
A
M
J
J
A
S
O
N
D
fallwinter