How to Plant and Grow Stokes' Aster

Stokes' aster, also known as stokesia, is native to the southeastern United States. It begins blooming sporadically in late spring but is prized for its midsummer and fall flower show. A favorite stopping point for pollinators, Stokes' aster has lavender, pink, or white cornflower-like flowers. Wonderful for cutting flowers and a great drought-tolerant plant for native and wildflower plantings, Stokes' aster is a showy, reliable perennial. 

Where to Plant Stokes' Aster

A heritage plant favored in cottage gardens, Stokes' aster grows best in full sun or part shade and fertile, well-drained soil. It’s an ideal selection for a pollinator or butterfly garden, perennial border, or massed in a native garden. Tolerant of damp sites, it can also be grown in a rain garden or by the side of a pond.

Reinvigorate the garden in late summer with Stokes' aster. Pair it with other fall favorites and the autumn garden will close the growing season in blooming style. If late summer- and fall-blooming perennials burst into bloom earlier than anticipated, deadhead the plants as soon as the blossoms fade to encourage another round of flowers to develop.

How and When to Plant Stokes' Aster

Plant Stokes' aster in the spring after the last average frost date in your region. To transplant a seedling or nursery specimen, dig a hole about the same width and depth as the planting container. Remove the plant and loosen the roots a bit from the root ball before placing in the hole. Backfill with soil, tamp lightly, and water well.

Space multiple plants 20-24 inches apart.

Stokes' Aster Care Tips

Among the showiest of the aster species, Stokes’ aster boasts blooms that are 2 to 4 inches wide and grows well in tough planting sites.

Light

Choose a planting site that receives at least 6 hours of bright sunlight a day for best blossoms. While the plant can tolerate partial shade, it will not bloom as vigorously.

Soil and Water

Stokes’ aster prefers a moist soil with good drainage. It’s not overly fussy about soil pH. After it establishes a strong root system, it is tolerant of both heat and dry conditions. It also manages well in occasionally wet soil.

In the absence of rainfall, water the plant deeply about once per week, allowing it to dry out between waterings.

Temperature and Humidity

As a native of the southeastern United States, this perennial can handle the heat and humidity of a hot summer.

Stokes' aster is hardy in winter down to zone 5 but at the lower end of its range, cut stems back to basal foliage and cover plants with a thick layer of mulch in late fall. Don't water the plant during dormancy; wet soil in the winter is the leading cause of death for Stokes’ aster.

Fertilizer

Fertilize each spring with a well-balanced, granular fertilizer. For the amount to use, follow product label directions.

Pruning

Remove spent flowers as soon as they droop to promote reblooming. Shear plants in midsummer, if needed, to create dense new growth.

Potting and Repotting Stokes' Aster

Select a container with large drainage holes that fits the root ball plus at least 2 inches to accommodate future growth. Fill it with a combination of well-draining potting mix and compost. Keep in mind that potted plants, unlike plants in the landscape, require more frequent watering and fertilization.

Once the roots of Stokes’ aster fill the pot, or grow out of the drainage holes, repot it in a large pot with a fresh potting mix/compost combination.

Pests and Problems

Stokes’ Aster has no serious insect or disease problems. Rabbits often devour Stokes' aster. If planted in an area with a large rabbit population, be sure to provide protection by installing a chicken wire fence.

Flower stems do tend to flop when wet, particularly after a heavy rainstorm.

How to Propagate Stokes' Aster

Plants can be divided every two or three years in early spring. To divide, dig up the plant and cut or break the clump into smaller sections with leaves and roots attached. Plant these into the garden at the same depth as the original plant and water well.

You can also increase your supply of Stokes' aster via cuttings. In spring, take 4-inch cuttings from the plant's stem tips. Remove the leaves from the bottom half of each cutting and dip it in rooting hormone. Put each cutting into a small pot filled with loose potting soil. Cover each pot with a clear plastic bag with air holes punched in it. Put the pots in a bright area (not in full sun) and keep the soil moist until the plants root. When you see any new growth, remove the plastic bag.

To grow Stokes' aster from seed, fill a tray with moist seed-starting mix about 6-8 weeks before your average final frost date. Cover with a thin layer of soil or vermiculite (about 1/8 inch is sufficient) and place in a warm spot or on a heat mat. At 70 degrees F, the seeds will germinate in 2-3 weeks and continue to sprout up to 5 weeks or so. Keep the soil evenly moist during germination and as the seedlings grow. When all danger of frost has passed, you can harden off your seedlings and plant them in the garden.

Types of Stokes' Aster

'Blue Danube'

Fluffy, sky-blue cornflowerlike blooms grow to 18 inches tall and wide. The flowers make a lovely addition to summer bouquets. Zones 5-8

'Alba'

This cultivar features snow-white flowers on multi-branched stems and blooms from June to September. Zones 5-9

‘Peachie’s Pick’

The lavender-blue flowers of 'Peachie's Pick' are butterfly magnets and bloom from midsummer to early fall. Zones 5-9

Stokes' Aster Companion Plants

Globe Thistle

 Globe thistle (Echinops ritro) is a joy to grow. This sun-loving perennial produces showy bright blue or white thistlelike spherical blooms from mid to late summer. The flowers also look beautiful in fresh or dried arrangements. Globe thistle is heat- and drought-resistant but doesn't transplant well, so plant globe thistle where you want it to grow permanently. The plants may self-sow if you allow the blooms to mature on the plant. Zones 3-8

Anise Hyssop

This tough, drought-tolerant perennial looks beautiful for months in summer and fall. That's when anise hyssop is covered with spikes of lavender-blue, licorice-scented flowers that pollinators love. It's also known as hummingbird mint because this mint family relative draws plenty of these winged visitors. Zones 4-9

Stonecrop

The fleshy leaves and spectacular flowers make tall sedum (also called stonecrop) a popular perennial. It's practically foolproof as long as the soil doesn't stay overly moist. It blooms toward the end of summer into fall when most other flowers are fading. Plus, the dried flower stems add winter interest if you leave them in place. Zones 3-10

Russian Sage

A tall, elegant summer bloomer, Russian sage bursts forth with feathery wands of violet-purple flowers over masses of silvery foliage. Like many other plants disliked by deer, it bears scented foliage. Zones 4-9