| Annuals
have insect and disease problems, and to maintain healthy and attractive
plants these problems must be recognized and control measures initiated.
The best method of reducing insect and/or disease problems is to keep the plants growing vigorously and free from stress. Cultural practices that should help to reduce insect and disease problems are as follows: 1. Select a planting site which provides desirable growing conditions for a particular annual. 2. Avoid planting in corners where light intensity and air circulation are minimal. 3. Keep plants growing vigorously by following a regular fertilization and irrigation schedule. 4. Avoid frequent wilting since water-stressed plants are more susceptible to infestation by thrips and red spider mites. 5. Remove spent flowers from plants such as marigold, salvia, snapdragon, and geranium, which do not naturally fall from the plant. 6. Prevent pathogenic fungal spores from germinating by keeping water off plants as much as possible and providing good air circulation around plants by allowing ample space between plants at planting. 7. Remove weeds from flower beds since they are frequently host to insects and/or disease organisms. Annuals should be monitored frequently for insects and diseases. Infestations detected in the early stages can be controlled before the entire flower bed is infested. An insect infestation on a few plant be controlled by picking insects off by hand or in the case of disease, by removing infected leaves. For severe infestations, chemical control will be needed. Contact your local County Extension office for recommendations on selection and application of pesticides. Return to Plants with Dr. Shummie |