One of the first questions new gardeners ask is, “How do I keep bugs out of my garden?” Well, you don’t. Insects have refined senses and many can fly long distances, so keeping insects out of a garden is not a realistic goal. Besides, you need them. A complicated food chain exists from the soil to the treetops, and insects are an essential part of a healthy ecosystem. Some are bad guys that damage plants or spread disease, while many more are allies in pollination and overall pest control.
What you don’t need are scads of damaging insects and a short list of beneficials, which is what you may get if you use pesticides that kill a wide range of life forms. Instead, long-time organic gardeners report success achieving a healthy balance between harmful and helpful insects by growing an abundance of herbs and flowers in or near their vegetable gardens. Many more tips for attracting beneficial insects are given in the profiles of common beneficials.
Even in the healthiest gardens, a few pest insects can be expected to require intervention. Identifying pest insects may be easier than you think, because most insects are able to feed on a narrow range of crops. For example, cabbage worms feed only on cabbage-family crops, while squash bugs stick close to squash. Most of the worst vegetable garden pests feed upon only one plant family.
The 15 pests discussed below are common in a wide range of climates, so you should not be surprised to encounter them in your garden. After you identify them, look closely to see whether beneficials are at work. Proceed to handpick if the pest populations are increasing, or if you know they will from your own experience. Keep notes of when pests appear in your garden, and be ready to prevent problems in future seasons by using floating row covers or changing your planting dates. You will find many other techniques for managing insect pests in these pages, as well as links to appropriate organic pesticides accepted by the Organic Materials Review Institute (OMRI).
Learn how to control a colony of aphids by attracting beneficial insects, learning organic pest control, and being able to recognize aphid damage as soon as it appears.
If your asparagus patch looks weak and unhealthy, chances are the asparagus beetle has struck again. Protect your crop with organic pest control methods, such as attracting beneficial insects and spraying neem. Plus, learn to recognize asparagus beetle damage before it’s too late.
Cabbage worms beat brassicas and consume cauliflower like nobody’s business. To defeat this garden pest, you must first learn how to identify it and then invite its natural enemies to live in your garden. Trust us, these neighbors won’t get along.
Colorado Potato Beetle
You can protect precious nightshade vegetables from Colorado potato beetles by learning how to attract beneficial insects to your organic garden, and by utilizing crop rotation and floating row covers.
If you see small green worms wriggling around on your corn, changes are they’re corn earworms. Learn how to prevent corn earworm damage and naturally treat infected crops.
As soon as cucumber family crops become available, the cucumber beetles find them and begin to feed. This is your cue to bring out the artillery; row covers and kaolin clay should be your first line of defense.
Cutworm collars made from plastic drinking cups or cardboard tissue rolls help protect young seedlings from cutworm damage.
Grasshopper damage can devastate organic gardens, particularly in areas with hot, dry weather. Learn how to use floating row covers and other organic gardening techniques for effective grasshopper control.
Learn how to use organic pesticides and attract natural Japanese beetle predators such as the Tiphia wasp to control the Japanese beetle population in your garden.
Mexican Bean Beetle
Create habitat for beneficial insects such as spined soldier beetles, tachinid flies and parasitic wasps to help with organic Mexican bean beetle control.
Garden slugs chew irregular holes with smooth edges in plants, and the damage often appears overnight. Try these slug control techniques to protect your crops.
Squash bugs love pumpkins and squash, and they will sabotage the leaves, stems and fruits of these autumn favorites. For a pest-free squash patch, follow these expert tips for organic squash bug control, including handpicking and installing row covers.
Squash Vine Borer
Squash vine borer damage can be devastating to pumpkins and squash. Protect your patch by learning how to recognize damage before it’s too late, and by handpicking and using row covers.
Many beneficial insects enjoy feasting on young tomato hornworm caterpillars, including yellow jackets, lady beetles and green lacewing larvae. By attracting these helpful insects and implementing additional controls, such as handpicking and row covers, pesky tomato hornworms could soon be a thing of your gardening past.
Wilting leaves in your garden may be a sign of whitefly damage. Learn how to implement controls such as yellow sticky traps, reflective mulch, and insecticidal soap.
Spotted a Bug in Your Garden?
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Even More Articles About Common Garden Pests
Our nationwide reader survey reveals the best methods for managing common garden pests.
Look to your backyard flock for the best natural pest control around.
Interplant flowers with your food crops to promote a balanced insect ecology and achieve natural insect control without toxic pesticides.