Plant Autumn Sun Cutleaf Coneflower in full sun to partial shade. Space plants 18-24 inches apart. Use well-drained, fertile soil. Water regularly, especially during dry spells, but avoid waterlogging. Fertilize in early spring with a balanced fertilizer. Deadhead spent blooms to encourage more flowers. Cut back stems in late fall or early spring to promote healthy growth. Divide clumps every 3-4 years to maintain vigor.