Plant Pathology Infobytes
May 10, 1996
Home Garden Fungicide and Insecticide Spraying Tips
Gardeners generally rely on fungicides and insecticides as the first line of defense against fungus and insect pests which cause problems in gardens, orchards, home landscapes. These materials are available at garden supply stores as wettable powders, liquids, and other formulations. When diluted with water at recommended rates and sprayed onto plants, fungicides and insecticides provide protection from many disease and insect pests.
Since it's the time of the year when many home gardeners are getting ready to handle plant pest problems, the following tips will help make fungicide and insecticide spraying a lot more effective.
- To avoid plant injury and unwanted residues on vegetables and fruit, never apply fungicides or insecticides through a sprayer if it has been used previously to apply herbicides. Herbicides residues are difficult to remove from sprayers, so it's best to have separate sprayers. One for herbicides, and another for fungicides and insecticides.
- Another rule to follow about fungicide and insecticide applica- tion is never mix up more spray than will be needed at one time. For example, when only a few plants need to receive a fungicide spray, consider using a one quart "squeeze-type" plastic sprayer. These are widely available and have an adjustable nozzle to allow application of sprays ranging from a fine mist to coarse droplets. If you only have three or four tomato plants or a few roses, it's just not practical to mix large quantities of fungicide spray and a quart or less will do the job just fine. And you'll save money, too.
- If you need to spray both a fungicide and an insecticide, use a combination spray. Most fungicides and insecticides are compatible. This means they can be mixed and sprayed onto plants at the same time, thus avoiding the need for separate applications. But there are exceptions, so check product labels closely for statements that warn against this practice.
Check with us at your county Extension office for more tips on how to control pests of garden, orchard, and landscape plants.
Infobytes newsletter was written by the late Dr. Frank Killebrew, Extension Specialist.