How to Garden With Mums in North Carolina

Plant small mum plants in spring after final frosts, or plant large, container-grown plants in spring, summer or fall. Mums needs a full-sun site with rich, well-drained soil. To improve thin sand, chalk soil and heavy clay, till into the planting site: 2 to 4 inches of well-rotted barnyard manure, peat moss or compost. Space plants 18 to 24 inches apart, according to the dimensions when mature.

Water mums thoroughly at planting and throughout the growing season, so that the ground is evenly moist, but not sodden. Apply a 2-inch mulch of garden compost, leaf mold or other organic matter to help retain moisture.

Feed mums weekly with a soluble fertilizer that boosts flowering, such as a 15-30-15 fertilizer, diluted at a rate of 1 tablespoon per gallon of water or according to manufacturer's instructions.

Pinch off the tips of shoots with your thumb and forefinger, removing about 1/2 inch of each stem. Doing so will produce bushy plants and aid prolific flowering. Pinch shoots again when stems have grown 6 inches. Stop pinching out in mid-June for early-flowering cultivars, late June for September-flowering plants, and early July for mums that flower in October.

Check mums regularly for signs of pest attack, such as holes in leaves or deformed foliage or buds. Chrysanthemum aphids (Macrosiphoniella sanborni), dark brown, shiny, soft-bodied insects about 2 to 2.5 mm long, can attack plants in North Carolina. The aphid aphid nymphs are dull, brick red, and have relatively long legs and antennae. Natural enemies often control minor infestations in outdoor mums. For heavy infestations, non-toxic insecticidal soaps are available which also deal with other potential pests such as leafhoppers and spider mites.

Protect overwintering mums with a 4- to 6-inch mulch of hay, straw, shredded leaves or evergreen branches once the soil surface freezes. Alternatively, dig up and discard plants once they have finished flowering and plant new plants next year.