Shining coneflowers (Rudbeckia nitida ‘Herbstsonne’), like all echinacea varieties, are a member of the aster family. They produce large, daisy-like yellow flowers, and can reach nine feet high and three feet wide, making them almost shrub-like in their growth. They are very sturdy, low-maintenance plants that produce blooms from mid-summer to late fall. They self-seed readily and attract bees, butterflies and even deer. Remember to give them plenty of room, and plant more than one because coneflowers can’t pollinate themselves.
Plant shining coneflowers in early summer through mid-summer in temperate zones, allowing the plants time to become established before fall weather arrives. In warm climates, plant coneflowers in the fall, according to Clemson University. Plant them in a sunny, or partially sunny location, with well-drained soil. Amend heavy soils with compost and peat moss.
Apply one lb. of slow-release fertilizer (12-6-6) per 100 square feet of garden bed to the soil in spring when new growth emerges. Scatter the fertilizer on the ground by hand and till it lightly with a hoe. Water the fertilizer to activate it. Echinacea plants are native wildflowers, and as such, don’t require highly fertile ground. If your soil is very poor, however, add two inches of compost every spring, as well, to improve drainage and texture.
Water the plants weekly, or as needed, to keep the soil slightly moist. Shining echinacea may require more water initially, but is drought tolerant once it is established, showing new growth and strong stems.
Remove the seed heads to promote more blooms, but leave them on the plants in late summer when flowers dwindle. They’ll provide a tasty snack for wildlife before winter arrives.
Cut coneflowers back after the first frost. Dig them up with a trowel or shovel and divide them every three to four years if they become crowded.
Spray the plants with an insecticidal soap if aphid infestations become severe. Hand-pick Japanese beetles and drop them in hot water or kerosene. Coneflowers are prone to powdery mildew and root rot. Remove diseased plant parts and clean up any garden debris to control diseases.
Plant coneflowers from seed started indoors, or nursery purchased plants.
Space shining coneflowers at least three feet apart. Good air circulation helps prevent disease in the flower garden.
Shining coneflower is hardy in USDA Plant Hardiness Zones 5 through 8. Try purple coneflower or black-eyed Susan if you live further north.
Plant shining coneflower at the back of the perennial garden. It creates a charming backdrop for smaller flowers.