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Willow Blue Star

Herbaceous Perennial Flower, Wildflower

Also known as Blue Star, Willow Amsonia
Amsonia tabernaemontana
Apocynaceae Family

Delicate, pale blue, star-like blooms and graceful, upright foliage (turning yellow in fall) make this eastern U.S. native a low-maintenance beauty. Chosen by the American Horticultural Society as one of the 75 Great Plants for American Gardens.

	Site and Plant Characteristics
	Growing Information
	Varieties

Site Characteristics

Sunlight:

full sun
part shade

In full sun, keep soil moist but not soggy. Plants grown in part shade require more pruning to maintain shape.

Soil conditions:

requires well-drained soil

Prefers rich, well-drained soil that is kept moist but not soggy.

Hardiness zones:

3 to 9

Plant Traits

Lifecycle: perennial

Ease-of-care: easy

Height: 1 to 3 feet

Spread: 1 to 2 feet

Bloom time:

late spring
early summer

Flower color: blue

Icy-blue flowers are star shaped.

Foliage color: medium green

Foliage texture: medium

Shape: upright

Shape in flower: same as above

Flowers are borne in clusters on erect stems.

Special Considerations

Special characteristics:

deer resistant
non-aggressive
non-invasive
native to North America - Eastern U.S.

Growing Information

How to plant:

Propagate by seed, cuttings, division or separation - Plants don't need to be divided often, but this is a good way to propagate plants. Divide in spring or fall while plants are dormant. Make sure each division has at least one "eye."
Take stem cuttings in late spring or early summer.
Seed requires 4 to 6 weeks of cold treatment for good germination. Sow in containers in cold frame in fall or spring.

Maintenance and care:

Cut back by a third to a half after flowering to maintain shape and keep plants from flopping over, especially in shady plantings. Deadhead or remove seedpods to prevent self-seeding.
More growing information: How to Grow Perennials

Diseases:

Rust

Varieties

var. salicifolia (sometimes listed as A. salicifolia) has narrower leaves.