Growing Blue Star Amsonia: How To Plant, Care Tips, ID Types of Bluestar

Image Credit: Daderot¹⁷

Growing a Blue Star From a Seed, Cutting, or Seedling

You can purchase seedling plants, but it’s not too difficult to get started from seeds.

Harvested seeds should be planted in spring. To grow a Blue Star from a seed, you will need to jump-start the germination process.

Snip off the end of the seed and soak it in water for two or three days to soften the shell.

Afterward, plant the seed half an inch deep into moist soil. Keep the soil moist for the first few months.

Seedlings will come with a good amount of root growth already established. After the threat of frost has passed, you can transplant the seedling to its outside location where it will get ample sunlight.

Keep the soil moist and provide some shade for the tender new growth until it has established itself; usually three months.

To grow an Amsonia from a cutting, cut off a section of new growth, just below the leaf node of the parent plant. Strip away the leaves and stems from the bottom half of the cutting.

Dip the cut end into a rooting hormone, and plant it two inches deep into a container of moist soil. The cutting should be ready to transfer to its final location within two months.

Best Growing Conditions for Blue Star

Blue Star Amsonia grows best in gardens that mimic their natural environment, areas with moist, sandy soil. Soil should be moist, but not soggy.

These plants can tolerate a wide variety of soils including clay and can be very drought tolerant once established.¹²

While they can grow in shade, they produce greater amounts of blooms with six to eight hours of full sun.

Tips for the Best Blue Star Growing Zone (Blue Star Amsonia Grow Zone)

The best zones for growing Blue Star are three through nine. These areas have cold temperatures that stay above -30℉.

They prefer warmer temperatures that are 55 to 65 degrees.⁸ Choose a Blue Star species that is native to your growing zone to make sure the plant will survive the dormant winter season.

Blue Star Growth Rate

Amsonias are slow growers, taking two or three years to reach full maturity. Seeds take 10 weeks to sprout,⁷ while seedlings won’t fully bloom for one to three years.¹²

Companion Plants For Growing Blue Star

Being short in stature and fairly delicate in appearance, Amsonias look great beside companion plants with wider leaves and blooms.¹² Irises, daylilies, and mums are heavier plants that contrast the Blue Star.

In addition, ferns and bleeding hearts compliment the Blue Star’s delicate blooms. Plant multiple Amsonias twelve inches apart.⁷

How To Stop Blue Star Disease

Blue Star Amsonia is typically resistant to disease. However, it can sometimes contract Mychosphaerella leaf spot and rust,⁹ which usually occurs in the humid temps of late spring or late summer.

Mychosphaerella fungi are brought in from overhead watering or rain. To prevent fungal infections, water at the ground level to keep the leaves and stems dry.

Blue Star disease prevention won’t kill the plant, it can cause leaves to fall off and be unsightly. Simply prune away and discard the affected foliage.

Treatment of fungal rust is vital as rust can damage the overall health of the plant and stunt its growth. You can use fungal herbicides to protect the healthy parts of the plant, but any affected parts will need to be trimmed away and thrown away.

You will also need to remove fallen leaves and nearby mulch since rust spores can overwinter in the soil.

How To Identify Blue Star Plant

Multiple stems emerge from the soil in early spring and grow straight up, unfurling their leaves to give the plant a bush-like appearance.

(Seed Image: Flobbadob¹⁶, Blue Star Amsonia Image: Anne Nygård¹⁴)

In Spring, blue flowers appear, and in late summer, distinct seed pods form. Throughout Fall, the leaves fade to varying shades of yellow or gold.

Identifying Blue Star Leaves

Amsonia’s slender leaves are roughly six inches long. They alternate along a pronounced center rib.

The common Blue Star has bright green leaves. If damaged, the leaves and stems secrete a latex-like sap that causes skin irritations in animals and humans.

Identifying Blue Star Flower

Amsonia flowers bloom in small clusters, each flower measuring ¾ of an inch wide.¹² The star-shaped blooms have five narrow and pointy lobes.

(Image: Meece Family (drmeece)¹⁵)

Their insides have a ring of fine hairs to deter crawling insects.

Identifying Blue Star Seeds

Pollinated flowers give way to long, erect oval seed pods four to six inches long. Each pod contains eight to ten brown seeds.

Blue Star Amsonia Plant Varieties

While all Blue Star Amsonia plants grow an average of two to three feet and bloom through late spring and early summer, you can choose from various Blue Star species to develop specific color themes in your backyard garden.

1. The Willow Leaf

The Willow Leaf is the most common variety,³ taking its name from its long, slender willow-like leaves. It has light blue flowers and its leaves fade to a pale yellow in the fall.

It can be found growing across the eastern and central regions of the United States.

2. The Eastern BlueStar

The Eastern Bluestar variety has pale blue flowers In the fall,⁴ the leaves turn golden-yellow.

It grows in the Northeastern and Midwestern regions of the United States

3. The Amsonia hubrichtii Blue Star

This variety has long, needle-like leaves that give it a feathery look.⁵ Native to Arkansas and Oklahoma, the hubrichtii species has light powdery-blue blooms but its leaves are bright gold in the fall.

4. The Blue Star Fringe

The Blue Star Fringe takes its name from the appearance of fine hairs that occur on new growth.⁶ It grows primarily in the southeastern parts of the United States.

More varieties have different shades of blue flowers and golden leaves.

Why Is It Called Amsonia tabernaemontana?

The Amsonia is named after John Amson,¹ physician and amateur botanist. In 1758, Amson treated General Washington for a common cold, clearing him to return to service.

In honor of his diagnosis, Amson was honored by having the Blue Star named after him.

Tabernaemontana is the genus name for these flowering plants and was the Latinized name of botanist J.T. Muller, from the term “tavern in the mountain.”²

Whether you’re designing a color-themed home garden or a backyard butterfly oasis, the native Blue Star Amsonia is a low-maintenance ornamental perennial that provides a year-long appeal.

Frequently Asked Questions About Blue Star Amsonia