Articles

Rain Garden Plants: Threadleaf Bluestar

One-page informational sheet with details and pictures of threadleaf bluestar (Amsonia hubrichtii).
Updated:
May 9, 2022

Long-lived plant with very fine, feathery foliage that turns golden in the fall. Clusters of steel-blue flowers bloom in May and June. Best when massed. Can be cut back in the spring for denser growth. Good nectar source for butterflies. No insect pest problems.  

Height: 36 inches
Bloom color: Light blue to almost white
Bloom time: April to May
Hardiness zone: 4 to 9
Salt tolerance: N/A
Spreading habit: Self-seeds; upright, bushy mounds

Close-up of Threadleaf Bluestar blossoms
Photo by Jodi Sulpizio, Penn State Extension
A clump of Threadleaf Bluestar
Photo by Jodi Sulpizio, Penn State Extension

Site Conditions

Sun: Sun/partial shade
Soil: Alkaline, moist, well-drained
Hydrologic zones: Moist/dry; occasional flooding

Threadleaf Bluestar plants
Photo by Jodi Sulpizio, Penn State Extension
A large cluster of Threadleaf Bluestars
Photo by Jodi Sulpizio, Penn State Extension

Source

The Morton Arboretum

Prepared by Jessica Chou, Jodi Sulpizio, and Constance Schmotzer.