Chrysanthemums planted or propagated in the spring require repeated pinching to create nice, low, bushy plants for fall. These are small, soft-bodied, rounded insects that damage mums by sucking juices from the plants. Feeding also causes stunted, curled or distorted growth. Aphids feed on young shoots, stems, undersurfaces of leaves, buds and flowers. Several species can attack mums including the brown to black-colored chrysanthemum aphids and the greenish to pinkish green peach aphid.
Aphids have many natural enemies such as the lady beetle and lace wing.
Different caterpillars may be a problem from year to year. The caterpillars chew holes in the leaves and stems, and some may bore into the stems. These very small pests feed by sucking juices from the undersurfaces of leaves. Mites are most damaging during the summer months since they favor hot, dry weather. A fine webbing is apparent in extreme cases as the mites travel over the webbing.