Bug Off!

Here’s a growing idea for green-minded gardeners: release praying mantis, ladybugs, parasitic wasps and other insects in your garden to prey on and eliminate insects that damage plants, without the use of pesticides.

“Compared to last year at this time, I’ve increased sales 20 percent,” says Don Cotton, general manager of Buglogical in Tucson, Ariz., a company that provides beneficial predatory insects, or beneficials. “More and more people are becoming aware of alternatives. I’ve even had pesticide companies that call me asking for beneficials because their customers don’t want pesticides.”

The growing popularity of certified organic produce is one reason for the bug boom. Many organic farmers cannot use pesticides, relying instead on beneficial insects to rid their plants of pests or washing them off themselves.

“The benefit of beneficials is that you don’t have the pesticides that will affect the groundwater or any other plant material,” says Susan Jett, director of horticulture at Rancho Santa Ana Botanic Garden in Claremont, Calif.

“It makes for a healthier system and a healthier garden, in that you don’t have insects that build up a resistance to chemicals, forcing you to resort to ever more toxic methods of treatment, which can really become a dangerous thing.” Beneficials are available in nurseries and home/garden stores in many areas of the country. They can be used to target problem insects in various regions. Cotton, who does business all over the country, says the most problematic pests can be combated with a variety of beneficial insects.

Grubs, which can damage trees, plants and the lawn, are best combated with beneficial Nematodes - microscopic worms that penetrate the body walls of an insect and release bacteria that kills the grub.

Aphids can destroy most any plant and flower, including citrus crops, vegetables, ornamentals, most any perennial and annuals. They can be eliminated with praying mantis and ladybugs. A single ladybug can consume up to 50 or 60 aphids a day and up to 5,000 in a lifetime. Cotton says it is best to apply ladybugs before temperatures rise above 90 degrees, as they will get too hot and fly off into the mountains. Green lacewings, however, will consume aphids in their larvae stage in hot areas.

“It’s always best to release ladybugs in late afternoon,” says Cotton. “It’s a little cooler and they have time to settle down. Mist the plants with water when you release the ladybugs so they have water.”

Another harmful insect is the spider mite, which Jett says occurs mostly during summertime and can damage fuchsia, vegetable crops, annuals and perennials. Both Jett and Cotton suggest using predatory mites and predatory wasps to combat these insects. But if you bring in all these insects, aren’t you just creating a new infestation in your garden? Not so, say Jett and Cotton.

“Once they’ve eaten the food source, they’ll go someplace else,” says Cotton. “It’s not really a concern with overpopulation of beneficials, it’s not having enough beneficials.” Jett points out that ladybugs and praying mantis do not even eat plants: “I think it’s just that people think bugs are bad for plants, and that’s certainly far from the truth.”