Sedum 'Harvest Moon' is a low stonecrop with tiny silver and purple succulent rosettes that hug the ground, topped with yellow, star-shaped flowers in late summer. At 4 to 8 inches tall and planted 8 to 10 inches apart, it knits into a cushion of sculptural rosettes that holds color even before it blooms, which makes it as useful for its foliage as for its flowers.
It wants full sun and fast drainage, and is easily lost in heavy or soggy soil. It suits rock gardens, wall crevices, gravel beds, edging, and shallow containers, where its muted foliage sets off brighter plants. Bees and small pollinators visit the summer flowers. Leave the plants alone through winter, trim off spent flower stems in late summer, and propagate by pulling off rosettes or taking stem cuttings in spring.
Root rot
Plants wilt, yellow, and stunt even in moist soil; lower stems and roots turn brown, soft, and mushy and the plant may collapse. Most common in heavy, wet, or poorly drained ground.
Improve drainage and stop overwatering, and never plant too deep. Lift and destroy badly affected plants along with the soil around the roots. Grow in raised or free-draining beds to prevent it returning.