Of the many asters, Stokes' is special
By JANE WEBER
Published March 26, 2007
Asters are among the prettiest colorful flowers in the garden. The family Asteraceae or Compositae is large and complex. Many plants that gardeners once lumped together as asters have now been sorted into separate genera.
For example, the bedding plants commonly named China asters are now in the genus Callistephus while purple cone flower, a Florida native, is Echinacea purpurea.
Stokes' aster, Stokesia laevis is special: There is only one species in the genus named after British Dr. Jonathan Stokes (1755 -1831). This perennial evergreen wildflower can bloom from spring through summer until early fall with masses of blue blooms, 2 to 4 inches wide, on 18-inch-high stalks.
As with many plants, removing spent flower heads prolongs the flowering season. Stokesia lures butterflies and hummingbirds with sweet nectar.
The dark green leaves form a basal rosette attractive in all seasons. Leaves are alternate and form 1- to 2-foot-clusters that get larger over the years. In four or five years the plant will need to be dug up and divided into several parts.
Plant small clumps 2 feet apart so they have room to grow.
They can grow in full sun provided the soil is acidic, rich in humus or natural organic matter and well drained. The leaf color is darker if in part shade.
Frost hardy in zones 8 and 9 in central Florida, Stokesia's natural range is from northern Florida, across the Panhandle west to Mississippi and north to South Carolina. A popular landscape plant, it prospers in central Florida but not in the hot, torrid South.
As it prefers moist sites, it relishes weekly irrigation but does survive in one of my xeric flower beds next to the driveway where I amended the sandy soil with compost and it gets afternoon shade from taller coonties planted nearby.
I top mulched around my plants with pine straw to deter sprouting weed seeds, shade the soil in summer, disburse heavy rainfall, retain moisture and help insulate in winter.
In recent years, several growers have propagated white and lavender flowered plants from selected parent plants.
Seedlings don't necessarily have the same color as the parent, so a pure white plant needs division to produce clones of the same color.
Companion flowers in a natural garden include spiderwort, Tradescantia ohiensis; blue-eyed grass, Sisyrinchium angustifolia, a native iris; blanket flower, Gaillardia pulchella; tropical or red sage, Salvia coccinea; black-eyed Susans, Rudheckia species; St. John's worts, Hypericum spp.; blazing stars, Liatris spicata, and beach and narrow-leaf sunflowers, Helianthus spp. All are available at native plant nurseries and a few at big box stores.
Low maintenance, frost hardiness, and disease and pest tolerance make Stokes' aster a welcome addition to a wildflower bed and butterfly garden.
Editor's note: This weekly article has been provided by Jane Weber, professional gardener, grower, consultant, designer and environmentalist. This is the last column here, as the Citrus Times will no longer publish after April 1. Visit her Certified Florida Yard and Backyard Wildlife Habitat, 5019 W Stargazer Lane, Dunnellon. Call (352) 465- 0649.