Description & Overview

Native to central Illinois, Willowleaf Amsonia is a lovely plant. It looks similar to asparagus coming up in early spring with many stalks appearing from the ground, quickly reaching heights of two to three feet. The leaves are willow-like, green, and alternate. In late spring, stems are topped with a grouping of fuzzy flower buds that open to light blue, star-like clusters. Once blooming has passed, flowers are replaced by erect, long seedpods. Willowleaf Amsonia may also be known as Eastern Bluestar, Woodland Bluestar, or Blue Dogbane.

Core Characteristics

Category: Perennial

Wisconsin Native: No - Native to North America

USDA Hardiness Zone: to zone 3

Mature Height: 2-3 feet

Mature Spread: 2-3 feet

Growth Rate: Moderate

Growth Form: Clump forming, bushy

Light Requirements: Full Sun to Partial Shade

Site Requirements: Dry - moist, good drainage

Flower: Blue, star - shaped, 5 - parted, ¾" wide

Bloom Period: May – June

Foliage: Green, lanceolate, willow - like

Fall Color: Yellow

Urban Approved: Yes

Fruit Notes: Erect pod containing seeds, 4 - 6" long pod

Suggested Uses

Willowleaf Amsonia grows best in full sun but can tolerate some light shade. It prefers moist soil but does well in clay soil. It is a long-lived perennial. Typically, we are pleased when perennials last 5-10 years in the landscape, but Amsonia ranks up there with long-lasting perennials like daylilies, hosta, and baptisia, growing decades when sited correctly in the garden.

Willowleaf Amsonia is native to the southeastern and eastern US where it is naturally found in moist to wet soils along streams, meadows, and open woods. A long taproot and tolerance of urban pollution, clay, or sandy soils make Willowleaf Amsonia a solid and reliable choice in the landscape. It is easily grown and looks exceptional when planted in masses or as a backdrop to other plants.

A host plant to several moths, and attracting bees and hummingbirds, plant Willowleaf Amsonia in a pollinator garden.

With its longevity and adaptability, Willowleaf Amsonia is an excellent addition to any flower or cottage garden. Bright blue flowers are unusual and contrast with others nicely. As a bonus, the foliage also turns a beautiful clear, yellow gold for many weeks in the fall.

With a long taproot, Willowleaf Amsonia is drought tolerant once established. Plant alongside White Wild Indigo (Baptisia alba), Prairie Dock (Silphium terebinthinaceum), or Prairie Phlox (Phlox pilosa) in drier areas or a xeriscaping garden.

Native to central Illinois, Willowleaf Amsonia is a lovely plant. It looks similar to asparagus coming up in early spring with many stalks appearing f…
Native to central Illinois, Willowleaf Amsonia is a lovely plant. It looks similar to asparagus coming up in early spring with many stalks appearing f…
Native to central Illinois, Willowleaf Amsonia is a lovely plant. It looks similar to asparagus coming up in early spring with many stalks appearing f…
Native to central Illinois, Willowleaf Amsonia is a lovely plant. It looks similar to asparagus coming up in early spring with many stalks appearing f…

Wildlife Value

Ruby-throated Hummingbirds will visit seeking nectar, as do butterflies and Carpenter bees. Other visitors include Hummingbird moths, Hickory Hairstreak (Satyrium caryaevorus), Poecila Sphinx (Sphinx poecila), Apple Sphinx (Sphinx gordius) Northern Blue (Plebejus idas), Arogos Skipper (Atrytone arogos), Edward’s Hairstreak (Satyrium edwardsii), Silvery Checkerspot (Chlosyne nycteis), Pearl Crescent (Phyciodes tharos), American Lady (Vanessa virginiensis), Spring Azure (Celastrina ladon), Monarch (Danaus plexippus), and Striped Hairstreak (Satyrium liparops).

Willowleaf Amsonia is the host plant to the Snowberry Clearwing Moth (Hemaris diffinis), Great Ash Sphinx Moth (Sphinx chersis), Coral Hairstreak (Satyrium titus), and Northern Crescent (Phyciodes cocyta).

Maintenance Tips

Wear gloves when pruning because this plant will exude white latex that is irritating to sensitive skin.

Deadhead after flowering to prevent self-seeding (if spread is not desired) and to help stems from flopping over. Cut back stems down to a third to improve appearance. In the end, plants will recede into the ground each fall. You may choose to leave stems up or cut them down. Stems will break under snow load and don’t have much winter interest.

There is no need for fertilization. Over-fertilization will cause floppy stems.

Its deep taproot makes transplanting this species particularly difficult. So site it correctly the first time!

Native to central Illinois, Willowleaf Amsonia is a lovely plant. It looks similar to asparagus coming up in early spring with many stalks appearing f…
Native to central Illinois, Willowleaf Amsonia is a lovely plant. It looks similar to asparagus coming up in early spring with many stalks appearing f…

Pests/Problems

Black Walnut Tolerant: Yes
Deer Resistant: Yes
Rabbit Resistant: Yes

There is very little disease or insect pressure on Willowleaf Amsonia. The milky sap it secrets keeps the vast majority of foliage clean.

Deer and mammals tend to leave it alone because of the latex sap in the foliage.

Leaf Lore

The genus Amsonia was named after Dr. Charles Amson, an 18th-century physician, and scientific traveler. The specific epithet tabernaemontana honors Jakob Theodor von Bergzabern who Latinized his name to Tabernaemontanus.

Willowleaf Amsonia and Milkweed are in the same family Apocynaceae and have the same milky latex sap.

Companion Plants

Pair Willowleaf Amsonia with flowers with contrasting colors and textures such as Butterflyweed (Asclepias tuberosa), Geum (Geum spp.), Bevan’s Geranium (Geranium macrorrhizum ‘Bevan’s Variety’), Moonshine Yarrow (Achillea millefolium ‘Moonshine’), Wildberry Coral Bells (Heuchera ‘Wildberry’ PP31,222), Royal Catchfly (Silene regia), Stiff Coreopsis (Coreopsis palmata), Zagreb Coreopsis (Coreopsis verticillata ‘Zagreb’), Daylilies (Hemerocallis spp.), and Little Bluestem (Schizachyrium scoparium).

Native to central Illinois, Willowleaf Amsonia is a lovely plant. It looks similar to asparagus coming up in early spring with many stalks appearing f…
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Written by Beth DeLain