Pests in Gardens and Landscapes: Quick Tips
Insecticides are substances applied to control, prevent, or repel insects. Insecticides can be an important part of integrated pest management; however, some products can worsen pest problems or harm people or wildlife. Other products—often called less toxic pesticides—cause few injuries to people and organisms other than the target pest. The less toxic insecticides listed below should be a first choice when deciding to use pesticides to control insects. Always check product labels to be sure the pesticide is registered for your plant and pest situation.
Soaps (potassium salts of fatty acids):
Insecticidal soaps control aphids, whiteflies, and mites. To be effective, complete coverage of pests is needed and sometimes a repeat application is also required. Soaps come in easy-to-use spray bottles for small jobs.
Oils control aphids, whiteflies, mealybugs, scale insects, spider mites, psyllids, and thrips. Good coverage of pests and plants is required. Don’t apply to water-stressed plants or when temperatures are above 90°F. Petroleum-based oil products include superior, supreme, narrow range, mineral, and horticultural oils. Plant-based oil products include neem and canola oils.
Microbials are derived from microorganisms that cause disease only in specific insects.
Nematodes are microscopic worms, and certain types, mostly Steinernema and Heterorhabditis species, attack and kill lawn insects, clearwing moths, and carpenterworms. Because nematodes are living organisms, they are very perishable, so order through the mail to assure freshness.
Derived directly from plant materials, botanicals vary greatly in their chemical composition and toxicity, but usually break down in the environment rapidly.
Avoid these more toxic pesticides:
Minimize the use of pesticides that pollute our waterways. Use nonchemical alternatives or less toxic pesticide products whenever possible. Read product labels carefully and follow instructions on proper use, storage, and disposal.