Genus Amsonia

Amsonia tabernaemontana Photo/Illustration: Michelle Gervais

am-SO-nee-ah

Synonyms: Rhazya

Useful in a border, at a woodland edge, or in a wildflower garden, the genus Amsonia is made up of about 20 species of clump-forming perennials that bear long-lasting, narrowly funnel-shaped blue flowers that resemble small stars. They bloom from spring to summer. The leaves of some species turn vibrant yellow in the fall, adding another season of interest. The foliage is attractive throughout the growing season, regardless of fall color. Amsonia are native to woodland and grassland in southeastern Europe, Turkey, Japan, and the northeastern and central U.S.
Noteworthy characteristics: Good fall color in some species. Long-lasting blue flowers. Some are U.S. natives. Skin may be irritated by the milky sap.
Care: Amsonia tolerate any moist but well-drained soil in full sun to light shade. They are somewhat drought-tolerant.
Propagation: Divide in spring. Root softwood or basal cuttings in early summer. Sow seed in a cold frame in spring or autumn using containers.
Problems: Susceptible to rust.

Species, varieties and cultivars for genus Amsonia

Amsonia hubrichtii
(Arkansas blue star) Be the first to rate this plant

Hardiness Zones:

Arkansas blue star's delicate, willow-like foliage is topped with pale blue star-shaped flowers in spring. The light green foliage looks good all summer, turns a beautiful golden-yellow in fall, and can stand through most of the winter, adding interest especially when mixed with grasses and other attractive seedheads. It grows to almost 3 feet tall and wide.

Amsonia montana 'Short Stack’
(Dwarf blue star) Be the first to rate this plant

Hardiness Zones:

Chalk up another great plant introduction from the folks at Plant Delights Nursery in Raleigh, North Carolina. This dwarf blue star grows to only about half the size of the species, making it well suited for gardens with limited space. It performs best in full to partial sun and is appreciative of moist, well-drained soil. The sky blue flowers appear in early spring above the clean, dark green foliage. Try planting 'Short Stack' in a mess and along bed edges for a winning display.

Amsonia tabernaemontana
(Willow blue-star) Be the first to rate this plant

Hardiness Zones:

In addition to willow blue-star’s small but charming clusters of blue flowers in late spring, it has upright, willow-like leaves that turn clear yellow in fall.