Nontoxic insecticide alternatives
A variety of safer options will help keep insects out of gardens.
Thu, Sep 30, 2010 at 11:00 AM
Chemical sprays are not the only way to keep bugs from chewing holes in vegetables or killing flowering plants. There are plenty of alternative repellents and pesticides. First remember some insects are beneficial. Others are simply harmless, even if they swarm around a plant. However, if insects become a problem, here are some tips and solutions to clear out a garden.
How to choose and apply an insecticide
No single insecticide should be used for every pest problem. Only purchase commercial insecticides in small quantities for specific insects on particular plants or garden areas. Do not store large quantities of chemical pesticides in the house. Ask a local garden expert or cooperative extension office about your pest problem. If you can handle the problem, consider the least toxic option, read the label, and closely follow directions. Keep close records of insecticide usage in case of poisoning or property damage. Also apply these rules to controlling weeds, rodents, and other unsavory characters.
What's wrong with the most popular insecticides?
Roundup (glyphosate) and AAtrex (atrazine) are the most popular pesticides for home use.
- Glyphosate may cause human genetic damage. A French study found threats to human sex hormones and placental cells, as well as increased miscarriages. It also may cause blurred vision, nausea, headaches, dizziness and other reactions. Other studies connected the pesticide to a large tadpole die-off.
- The Environmental Protection Agency is considering banning atrazine. It has caused hormonal imbalances in lab animals and may have other biological side effects.
What are the alternatives?
Plants helping other plants: There are a few natural repellents that don't kill the bugs but will help keep them away from your garden. Plant marigolds and feverfew around vegetable and flower gardens. Most insects dislike the strong odor. Some types of pungent basil and sage also repel a variety of insects. Chives and nasturtium can keep aphids off rose bushes. Borage will keep worms out of tomatoes. Rosemary keeps away mosquitoes.
Foil insects: Strips of aluminum foil under vegetables will reflect light and confuse insects. The reflected light can also help vegetables grow.
Keep ants away: Ants may be annoying, but their threat to gardens is debatable. They dig around and loosen soil, which improves air and water circulation but might kill fragile young plants. Home insecticides for ants include oranges or hot chilies diluted in water, and concentrated vinegar. Pour each mixture onto an anthill.
Homemade sprays and solutions: If other home remedies fail, make a general homemade insecticide solution. For centuries, gardeners have put soap on plants to repel insects. Try diluting a one-percent solution of a simple dishwashing soap with minimal dyes and fragrances. Spray thoroughly and repeatedly on plants. Another popular solution is a mix of onions, garlic and pepper, but it has not been scientifically proven.
Natural chemical solutions: If you have to resort to commercial insecticides, look for non-toxic plant-derived products. Sabadilla may irritate your eyes and throat, but it is not considered toxic to humans. Neem extract is non-toxic and may have beneficial medical uses (but don't drink the insecticide mixes).
Instead of loading up the yard with toxic insect killers, consider the wide variety of alternatives, including soap, marigolds, aluminum foil and non-toxic chemicals.
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