Perennials for Clay Soil in Zone 4

Blue and Purple

• Blue stars (Amsonia tabernaemontana) tolerate clay soil. These 3-foot-tall perennials bloom in midspring with showy, star-shaped blue flowers. They're hardy in USDA zones 3 to 9 and grow well in full sun or partial shade. For purple blooms over clay soil, plant a pale purple coneflower (Echinacea pallida). Reaching heights of 3 feet, these perennials attract butterflies with their lilac flowers from late spring through midsummer. Hardy in USDA zones 3 to 10, pale purple coneflowers grow in sun or partial shade and tolerate drought.

Yellow and White

• Barren strawberries (Waldsteinia fragarioides) grow well in clay soil. These small perennials grow to 6 inches tall and bloom in spring with clusters of yellow blossoms. They're hardy in USDA zones 4 to 7 and thrive in full sun or partial shade. For vertical interest, plant a joe-pye weed or American boneset (Eupatorium perfoliatum). These clay-tolerant North American natives grow to 6 feet tall and bloom through summer and early fall with white blossoms. They prefer moist to wet soil and thrive in sun or partial shade. Joe-pye weed is hardy in USDA zones 3 to 8.

Red and Orange

• Attract bees and butterflies with bee balm (Monarda didyma), a clay-tolerant perennial that grows to 4 feet tall and 3 feet wide. Hardy in USDA zones 4 to 9, this native plant blooms from mid- to late summer with aromatic, bright red blossoms. Plant bee balm in sun or partial shade. "Prince of Orange" phlox (Phlox paniculata "Prince of Orange") blooms from late summer through fall with orange and red flowers. This 2-foot-tall cultivar is hardy in USDA zones 4 to 8 and grows well in clay soil and full sun to partial shade. It attracts pollinators with its showy blossoms.

Pink and Rose

• "Wood's Pink" asters (Aster "Wood's Pink") bloom from summer through fall with pink blossoms with yellow centers. Reaching heights to 18 inches, these clay-tolerant flowers require sunny sites and tolerate drought. For rosy pink flowers, plant a turtlehead (Chelone obliqua). This North American native tolerates clay and grows well in partially shaded, moist sites in USDA zones 3 to 9. Turtleheads grow to 3 feet tall and bloom in mid- to late summer with deep pink, white and purple flowers.