Content Detail

Eastern blue star is a long-lived, interesting perennial native to the central United States. Erect clumps of deep green, willow-like leaves add structure to the garden. Steel-blue star-shaped clusters open in late spring and foliage turns a beautiful golden yellow in the fall.

  • Family (English) Dogbane
  • Family (botanic) Apocynaceae
  • Tree or plant type Perennial
  • Native locale North America
  • Size range Large plant (more than 24 inches)
  • Light exposure Full sun (6 hrs direct light daily), Partial sun / shade (4-6 hrs light daily)
  • Hardiness zones Zone 3, Zone 4, Zone 5 (Northern Illinois), Zone 6 (City of Chicago), Zone 7, Zone 8
  • Soil preference Moist, well-drained soil
  • Tolerances Occasional drought, Occasional flooding
  • Season of interest mid spring, late spring, early summer, late summer, early fall, mid fall
  • Flower color and fragrance Blue
  • Shape or form Mounded, Narrow, Upright
  • Growth rate Slow

Native geographic location and habitat:

This is native to central U. S. from Massachusetts to Kansas into south Georgia and Texas. It grows in open, moist woodlands and along stream banks.

Attracts birds, pollinators, or wildlife:

This perennial attracts butterflies, hummingbirds, and bees.

Leaf description:

Leaves are alternate, willow-like, oval to elliptical, 3/4 inches wide and 2 to 4 inches long. They are dark green with a pale white to green midrib. The fall color is an outstanding clear yellow.

Flower description:

Dark blue buds open as periwinkle turning to steel-blue in drooping clusters of star-shaped flowers. Flowers bloom in late spring to early summer. Stems contain a milky sap. They make long-lasting cut flowers if the stems are dipped in boiling water to seal flower stalks.

Fruit description:  

The fruit is narrow seed pods which appear in pairs. Reseeding can be a problem, so shear off faded flowers to prevent seeds from forming.

Plant care:

This perennial requires full sun to light shade in moist, fertile soil. Once established it is tolerant of dry conditions and temporary flooding. Prune back to the ground in early spring. Faded flowers can be pruned in summer to prevent seed development. Stems contain a milky sap that can be a skin irritant. Staking may be required if planted in too much shade.

Pests, diseases, and tolerances: 

There are no known serious diseases or problems. This perennial is deer resistant.

Blue Ice Eastern blue star (Amsonia ‘Blue Ice’):

This variety is a compact, mounded form reaching 18 to 24 inches high and wide. It has dark blue buds opening to dark blue flowers.

Willow-leaf blue star (Amsonia tabernaemontana var. salicifolia):

This upright, erect cultivar grows 24 to 36 inches high. It has blue flowers with a white throat.

Ozark blue star (Amsonia illustris):

A southwest native with shiny, broad leaves reaching 3 feet high with light purple-blue flowers.

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