Heather (Calluna vulgaris) Small, single or double flowers appear in midsummer in 1- to 4-inch clusters. Many varieties. Flower colors include rose, purple, pink, white, and coral. Foliage is green or yellow, changing to bronze in the fall. Zone: 5 Light and Soil: Full sun. Tolerant of most soil types; prefers slightly acid soil. Height: 3' Comments Use in beds, foundation plantings, rock gardens, or as a ground cover. Mulch for best results. Prune in early spring before new growth begins.