Fall mums are very popular plants for late-season color and are available in a wide selection of shapes, sizes, flower types and colors. They are perennials that are easy to grow in garden beds or containers. Plant in full sun 24 inches apart. In early spring, remove dead branches down to the soil; and once your plants have reached 4 to 6 inches, remove the tops by pinching or cutting off about 1 to 2 inches of new growth on every shoot until mid July to keep the plants compact and delay flowering.