Common Name: water avens
Type: Herbaceous perennial
Family: Rosaceae
Native Range: Europe, northeastern America
Zone: 3 to 7
Height: 0.75 to 1.50 feet
Spread: 0.50 to 1.00 feet
Bloom Time: May to August
Bloom Description: Brown-purple calyx and cream to purple-pink petals
Sun: Full sun to part shade
Water: Medium to wet
Maintenance: Medium
Flower: Showy
Tolerate: Deer, Wet Soil
Culture
Grow in moist to wet soils in full sun to part shade. Prefers moist, fertile soils in cool climates. Needs afternoon shade in hot, humid climates. Tends to struggle with both summer heat and humidity south of Zone 7 where it is not recommended for planting. Likes boggy and swampy conditions. Not always reliably winter hardy in areas north of Zone 5. Plants may be propagated by seed or division. Deadheading spent flowers will encourage additional bloom.
Noteworthy Characteristics
Geum rivale, commonly known as water avens, purple avens or chocolate root, is a clump-forming herbaceous perennial of the rose family that typically thrives in boggy areas including wet meadows and swamps. It is native to Eurasia and North America (Labrador to British Columbia south to New Jersey, West Virginia, northern Illinois, Minnesota and in the mountains to New Mexico). It typically grows to 8-18” tall and features showy, nodding, bell-shaped, 5-petaled flowers (to 1/2”), 2 to 5 flowers per stem, which bloom late spring into summer (late May to early August) and compound dark green leaves. The brownish-purple calyx of each flower surrounds its cream to purple-pink petals. Each pinnate leaf has 3 to 6 pairs of small, lateral, unequally-toothed leaflets (1/4 – 3/4”), with a very large terminal leaflet (1-2” diameter) which is usually over twice the size of the lateral leaflets. Good ground cover for cool wet areas where many other plants often struggle. Will grow well in non-boggy areas as long as soils are kept consistently moist.
Genus name is the classical Latin name of the group.
Specific epithet means growing by streams.
If plant rhizomes are boiled in water, the resulting liquid has a faint taste of chocolate, hence the common name of chocolate root.
Problems
No serious insect or disease problems. May be short-lived in heavy clay soils and/or hot summer climates.
Uses
Mass in borders or rock gardens. Foliage makes an attractive ground cover after bloom.