Safely Pest-Proof Your Garden

Keep bugs away away naturally.


Effective integrated pest management (IPM) relies as much on prevention as extermination. Effective measures for reducing pests include introducing natural predators as well as depriving them of food, water or access.

By Vincent Standley and Paul McRandle. Reprinted with permission from The Green Guide.

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To get rid of pests, U.S. homeowners spend more than a whopping $2 billion a year on lawn and garden pesticides. Of 103.9 million U.S. households with lawns, more than half use insecticides; 40 million use herbicides and 14 million use fungicides. Many of these products threaten unintended targets, including people, animals, birds and fish. Studies indicate that even incidental exposures to these poisons, through touch or inhalation, may pose dangers, particularly to pregnant women and young children.

Synthetic pesticides are of particular concern because they attack the nervous system, can cause developmental delays in children, and are linked to cancers and hormonal and reproductive system disruption. Children who were frequently exposed to household pesticides—including some insecticides used on plants and lawns—had twice the risk of childhood leukemia as a control group, according to a French study (Occupational and Environmental Medicine, January 2006). Women who are pregnant—or who plan to be—have good reason to avoid pesticides in light of recent studies linking infertility, spontaneous abortion, preterm delivery and birth defects in lab mice with common pesticides including two fungicides (chlorothalonil and mancozeb), three insecticides (chlorpyrifos, terbufos and permethrin), a dessicant (diquat) and six herbicides, including 2, 4-dichlorophenoxyacetic acid (2,4-D), mecoprop, dicambra, metolachlor, pendi-methalin and atrazine.

It’s not just humans at risk. Frogs, salamanders, fish, birds and other wildlife are threatened by runoff from residential and agricultural lands. The U.S. Geological Survey has found that more than 95 percent of streams sampled contained at least one pesticide, and the contribution of nitrate fertilizer to “dead zones” in bays, gulfs and oceans has been well documented.

Drinking water also can be contaminated; atrazine, for one, has been found in groundwater throughout the country. And the herbicide glyphosate (used in Roundup), which kills nearly all plants and is toxic to earthworms, fish and several beneficial insects, is leading to more powerful, pesticide-resistant weeds.

Keep bugs away naturally

Even in light of this depressing news, you still don’t want your garden overrun by pests, so what can you do? Happily, nontoxic pest control and soil-enrichment alternatives abound, and gardeners are making use of them. The following tips can help you keep your yard truly green. Remember to handle all pest treatments, conventional or least-toxic, with caution, keeping them out of the reach of children and pets. Follow instructions carefully; use gloves and wear long sleeves and goggles as necessary. And wash your hands or shower thoroughly afterward.

Read labels to avoid toxic synthetic chemicals At a minimum, avoid products that contain some of the most dangerous and ubiquitous chemicals, including Ortho Weed B Gon, Bonide Weed Beater, Scotts Weed Control, Roundup, Rodeo, Accord and Touchdown.

Dislodge weeds with tools, not chemicals. Try the Wrist Easy Ergonomic Hand Rake and the long-handled Speedy WeederSpiked Lawn Aerator Sandals help improve soil health.

Buy less toxic herbicides Natural brands may contain acetic acid (vinegar), corn gluten, fatty acids and plant oils such as clove. Safer brands include TurfMaize to prevent crabgrass and dandelions from sprouting and St. Gabriel BurnOut Weed and Grass KillerCaterpillar Killer Concentrate employs a safe bacteria, Bacillus thuringiensis, that’s used by organic farmers.

Make your own less toxic insecticides Liquid soap kills aphids, sawflies, spider mites, scale and whiteflies. Mix two tablespoons of plant-based liquid soap (such as Dr. Bronner’s) with one gallon of water and spray. For extra strength, add a few drops of plant oils such as rosemary, peppermint or clove.

Try ground red pepper and powdered garlic or onion Soak two to five handfuls in a gallon of water, then filter out solid matter. Water your vegetables with the liquid two to three times a week.

Dehydrate crawling insects Use diatomaceous earth, a nontoxic powder made from the crushed fossils of single-celled, algae-like organisms. As insects crawl through diatomaceous earth, it lacerates their outer shells; they then dehydrate and die. Apply the powder around the edges of your lawn or at the base of plants.

Don't overfertilize. Eliminate ammonium nitrate fertilizers by using compost and leaving grass clippings on lawns.

Select plants that are native to your locale. Native plants often are resistant to area pests. Contact the nearest USDA extension office for free advice about local climate and growing issues. Ask if it sells soil-collection test kits, which help you choose plants to suit your soil.

General Information

Beyond Pesticides
• Northwest Coalition for Alternatives to Pesticides
• Pesticide Action Network North America
• U.S. Environmental Protection Agency
• Healthy Lawn Healthy Environment booklet
• “Nontoxic Lawn and Garden Product Report
• “Organic Land Care” brochure
• National Coalition for Pesticide-Free Lawns

Beneficial Insects

• Arbico Organics
• Beneficial Insects
• Biologic Company

Horiculture Supplies

• Bountiful Gardens
• Gardens Alive!

Pest Control and IPM

• Bio-Integral Resource Center
• Planet Natural
• Seabright Laboratories

Mindy Pennybacker is editor of The Green Guide , a print and online publication that helps people protect the environment and their families’ health through informed product choices and other actions.