Stokesia laevis aka Stokes' Aster

Stokesia laevis, or Stokes' aster, is in the daisy family. This plant lives for more than one year. It comes from the southeastern United States into eastern Texas. It grows in wetlands, low ground, and wet pine woods. It also grows in savannas and ditches beside roads. Much of its range lies along the coastal plain. Gardeners grow it for blue flowers and leaves that last.

Plants reach 1–2 feet [0.30–0.61 m] tall in gardens. They spread to about 1.5 feet [0.46 m]. The RHS gives a little lower height, near 1.6 feet [0.50 m]. Upright stems bear leaves and rise from a ground-level rosette. This is a cluster of leaves at the plant's base. These green leaves are narrow and shaped like a lance. They reach 6 inches long, or 8 inches in RHS accounts. Smaller leaves clasp the stems and have no leaf stalks. Leaves at the base have smooth edges. Those on the stems may have teeth. The rosette keeps its leaves through winter.

The flower heads look much like cornflowers. Their shades range from violet to lavender-blue and purple-blue. Small flowers called florets form each head. Notched outer florets ring a soft-looking center of disk florets. Missouri Botanical Garden reports heads up to 2.5 inches across. Chicago Botanic Garden gives a larger size: 4 inches across. Some accounts say bloom starts in early summer. Others place the main show later in summer. Flowers can last into early autumn and sometimes bloom again. Butterflies and bumblebees come to the blooms for nectar. Chicago Botanic Garden also lists birds as visitors.

Give this plant full sun and soil that drains well. It accepts some shade, but full sun suits it best. It prefers moist soil and grows in sand or loam. Acid to neutral soil suits its needs. It tolerates heat, drought, and brief spells of wet soil. Wet ground in winter can cause rot and plant loss. Chicago lists USDA zones 5–10; the RHS rates it H4. Winter mulch helps protect plants in colder parts of its range.

Use Stokes' aster at border fronts or in cottage gardens. Plant groups in native plant gardens or beds for pollinators. Moist pond edges suit it where water can drain away. Remove faded blooms and stems to encourage more flowers. Tidy old leaves when fresh growth appears in spring. Most sources report few pest or disease problems. Watch for caterpillars. Stems may flop after heavy storms. Plants resist rabbits but resist deer only to a moderate degree. Grow new plants from seed or divide them in spring. Root cuttings taken in late winter offer another way.