Many field, fruit, and vegetable crop pests such as the cabbage looper, corn earworm, diamondback moth, and oblique banded leafroller also feed on ornamentals. Lush growth and sheltered growing conditions make ornamental herbs especially attractive to plant pests. The routine use of insecticides usually eliminates predaceous insects and mites. However, pests remaining after treatment sometimes tolerate commonly used insecticides. To stay in business, most commercial flower and foliage plant growers must become fairly sophisticated in using various types of pest management practices, insecticide formulations, application equipment, and in rotating insecticides from one chemical group to another.
Commercial growers use a battery of general and restricted-use pesticides.
Although amateur gardeners battle the same pests, the most effective chemicals for control are often very expensive or are restricted so that homeowners are not allowed to use them. This puts a moral burden on the commercial grower to try earnestly to eliminate all plant pests from bedding, potted, and cut plants before selling them. These keys, plus the color plates and the illustrations in the insect notes, will help you to identify the pests of herbaceous ornamental plants. Identification is important to assure proper control measures. This manual is designed to augment state Cooperative Extension Service publications on pest management, not to duplicate them.