Thalictrum kiusianum
Common Name: meadow rue 
Type: Herbaceous perennial
Family: Ranunculaceae
Native Range: Japan, Korea
Zone: 5 to 8
Height: 0.25 to 0.50 feet
Spread: 1.00 to 1.50 feet
Bloom Time: June to August
Bloom Description: Lavender to pinkish-purple
Sun: Full sun to part shade
Water: Medium
Maintenance: Low
Suggested Use: Ground Cover, Naturalize
Flower: Showy
Tolerate: Rabbit, Deer

Culture

Best grown in organically rich, moderately fertile, medium moisture, well-drained soils in part shade. Less vigorous growth typically occurs in full shade. Will grow in full sun if given consistent moisture. May be grown from seed and will self-seed in the garden.

Noteworthy Characteristics

Thalictrum kiusianum, commonly called dwarf meadow rue or Kyoshu meadow rue, is a herbaceous perennial that is native to Japan and Korea where it is primarily found growing in moist woodland alpine areas. It typically forms a low-growing foliage mat (to 4-6” tall spreading by rhizomes to 12-18” wide or more) of tiny, bronze-tinted, 1-2 ternate green leaves (to 5” long) with toothed ovate leaflets. Plants have both basal leaves and smaller stem leaves. Tiny, starry, apetalous, lavender to pinkish-purple flowers (each to 1/3” across) bloom from mid June to August in fluffy many-flowered inflorescences (panicles). Plants are dioecious (male and female flowers on separate plants), except some plants may have bi-sexual flowers with limited numbers of stamens combined with flowers of only one sex or in some cases with flowers of each sex.

Genus name comes from the Greek word thaliktron which was a name used by Dioscorides to describe a plant in this genus.

Specific epithet is derived from Kyoshu (southernmost of the four main Japanese islands) where this plant is native.

Plants in the genus Thalictrum are commonly called meadow rue in reference to the similarity of their leaves to the leaves of common rue (Ruta graveolens). Leaves are also reminiscent of the leaves of columbine (Aquilegia).

Problems

No serious insect or disease problems. Powdery mildew, smut, rust, leaf miners, leaf spots, or slugs may appear.

Uses

Small area ground cover for moist and shaded areas of rock gardens. Path edger. Spilling over walls.