Pesticides can be valuable tools for garden and home pest control, but they must be selected and applied with both personal and environmental safety in mind. As with other tools, it is important to use the right pesticide for the job.
What is a Pesticide?
Pesticide is a broad term for the wide variety of substances used to kill, control, or repel pests. Pesticides include insecticides for control of insects; herbicides (weeds); fungicides (pathogens that cause plant diseases); rodenticides (mice and rats); and molluscicides (slugs and snails).
Is a Pesticide Really Needed?
The use of a pesticide should be the last resort for managing a problem. Start with preventative measures, such as selecting disease-resistant varieties or spacing plants appropriately to allow for good air circulation and reduced disease issues. Use mechanical controls such as fencing or netting to keep animals and insects away, or hand-pull weeds. Consider biological controls, such as predators or parasites, to reduce pest populations to a level where damage is not notable. Only after doing all of these actions should a pesticide be considered.
This holistic approach to problem management is referred to as integrated pest management (IPM). Learn more in this publication: Integrated Pest Management for Home Gardens and Landscapes (PDF)
Using Pesticides Safely
Due to their impact on your health and the environment, using pesticides safely is crucial. Learn more in this publication: Home and Garden Pesticide Guidelines (PDF)
Accurately Identify the Problem
Using pesticides safely starts with accurately identifying the problem. Spraying a fungicide won't help if the issue is caused by insects. The best pesticide can only be selected if the problem has been clearly identified
Many resources are available to help identify the problem (see below). When further help is needed, contact the Plant and Insect Diagnostic Clinic.
- How to Diagnose Problems with Trees in the Landscape
- Managing Problems in the Vegetable Garden
- Diagnosing Houseplant Problems
- Biotic vs. Abiotic - Distinguishing Disease Problems
Read & Understand the Label
It is essential to read and understand the pesticide label. Ensure the product you use is specifically designed for use on the plants to which it is applied. Take special care when selecting pesticides for use on edible plants. Never use a pesticide on a food-bearing plant unless the label directs such use.
Consider Where and How It's Being Used
Ensure the location where you are applying the pesticide is safe for its use. How will nearby plants, insects, wildlife, children, or pets be affected? Be sure the proper equipment is available for the application. Determine the exact amount needed and only purchase that quantity. Pesticides have a limited shelf life, and storing them can present a danger to you and your family. Finally, be sure to use the least toxic product that will still offer the control you need.
Apply Pesticides Safely
Always apply pesticides as outlined on the label using proper, well-maintained equipment. Always mix according to the directions (if 1 oz is specified, 2 oz is not better!). Mix in a well-ventilated area (preferably outdoors) away from other people and animals. Don't eat, drink, or smoke when mixing or applying, and always wear appropriate clothing, shoes, gloves, and eye protection (as indicated on the label, also referred to as PPE). Apply in appropriate weather (calm and cool) and clean equipment, clothing (PPE), and spills immediately.
Store and Dispose Properly
Proper storage of pesticides is crucial to protect human health, preserve the environment, and maintain the effectiveness of chemicals. Leftover, unused, or unwanted pesticide products must be disposed of at Household Hazardous Materials Regional Collection Centers.
More Information
- Understanding Pesticide Labels (PDF)
- Toxicity of Common Lawn, Garden, and Ornamental Pesticides in Iowa (PDF)
- Chemical Injury to Garden Plants
- Herbicide Injury to Garden Plants
- Insecticides in the Home Landscape and Garden
- Horticultural Oil Sprays
- Insecticides for Indoor Use
- Proper Fungicide Use
Photo credits: 1: Dmytro Titov AdobeStock; 2: Jammer Gene; 3: Dmytro Titov AdobeStock; 4: Scott Habermann AdobeStock