Living in a state with four recognizable seasons gives Ohio's gardeners the chance to exercise their garden design skills. Choosing Ohio perennials--plants that return year after year--provides bloom or foliage interest from spring to fall. Pairing different annuals with complementary or contrasting perennials is both challenging and fun. Use a linear calender, which shows every day of the year on one grid to determine when each perennials will bloom, suggests Ohio State University's Horticulture and Crop Science Department. You'll ensure an ever-changing and attractive garden palette.
Flowering in early spring, eastern bluestar (Amsonia tabernaemontana) is a 1- to 3-foot perennial of the dogbane family. This straight-stemmed clumping plant grows wild in Ohio's wet, sandy woods. Its oval green leaves provide yellow autumn color. Between March and May, says the Lady Bird Johnson Wildflower Center (LBJWC), loose clusters of star-shaped blue blooms top its stems. Yellow anthers (pollen holders) brighten the flowers. Plant eastern bluestar in a partially shady spot with moist, sandy soil.
As eastern bluestar's blooms fade in May, those of the Ohio spiderwort (Tradescantia ohiensis) open. This clump-forming perennial stands up to 3 feet tall and 30 inches wide, with attractive grassy blue-green foliage. From the end of May until July, Ohio spiderwort's stems bear clusters of three-petaled flowers. Living only a day, they're usually dark blue. Some plants, however, produce rose-pink ones.
Plant pest- and disease-resistant Ohio spiderwort in perennial borders or woodland gardens, recommends the Missouri Botanical Garden. It grows and flowers best in full sun with acidic (pH below 7.0) and moist sandy soil. Plants tolerate partial shade but bloom less. Cutting spiderwort back to within 12 inches of the ground in midsummer will keep its foliage tidy and encourage fall flowers.
Mealy Blue Sage
A mint family perennial, mealy blue sage (Salvia farinacea) grows in mounds up to 3 feet high and wide. Its stems arise from clumps of narrow, aromatic grayish-green leaves. From April to October, blue mealy sage has dense 3- to 9-inch spikes of fragrant white or blue flowers. The sage-scented blossoms attract hummingbirds and butterflies.
The LBJWC recommends deer-resistant mealy blue sage for perennial borders, rock gardens and wildflower meadows. Mass it in groups for best effect. It needs full sun and limestone-rich, acidic moist soil. Sand, loam and clay are acceptable. Keep plants looking their best by removing old flower heads when new foliage appears.
Common gaillardia (Gaillardia aristata), an aster family perennial also called blanket flower, stands from 2 to 4 feet high. Its toothed green leaves resemble those of dandelions, says the LBJWC. Daisy-like blooms appear from July to September. Their yellow petals have deep red bases, evoking thoughts of autumn colors to come. Plants like full sun and well-drained, dry infertile soil. The tiny hairs covering their surfaces may irritate the skin.