Organic Pest Control

Article Tools

Image Gallery

Print

E-mail

Comments

RSS

All of the possible answers to these three questions are called cultural controls, which can be remarkably effective. When Cornell University brought together five horticulture experts to summarize the effectiveness of organic pest-control options for 36 vegetable insect pests and diseases, they found that 20 often could be handled using cultural controls. In your garden, the ratio between problem pests and cultural solutions can get tighter as you learn to make use of practical preventive measures.

KNOW THY ENEMIES

It’s important to understand that most garden pests are only capable of damaging a very narrow range of closely related plants. For example, little black flea beetles may make holes in potato leaves in spring, then hop to tomatoes or eggplant in summer, but they won’t veer far from plants that are members of the nightshade family. In similar fashion, the squash bugs that invade your pumpkin patch cannot digest juices sucked from lettuce or broccoli. A few pests do have broad feeding ranges (Japanese beetles eat the leaves and flowers of more than 200 plants, and some grasshopper species have equally varied tastes), but for the most part, garden pests require the presence of specific host plants — that’s where you can target your efforts.

It’s wise to learn as much as you can about the life cycles and physiques of the pests that are damaging plants in your garden. Invest in a hand-held magnifying glass and a good insect identification book, such as Garden Insects of North America by Whitney Cranshaw. Also bookmark useful online resources. Two excellent places to start are Cornell University’s Resource Guide for Organic Insect and Disease Management and the University of California’s Integrated Pest Management Program.

To find local information, begin with the U.S. Department of Agriculture’s guide to regional integrated pest management centers. The Ontario Ministry of Agriculture, Food and Rural Affairs is bursting with good information on insect identification and control.

The more you know about your problem pests, the better job you can do choosing an intervention that will prevent or stop the damage without sabotaging the important work done by beneficial life-forms. Before you get excited about any pest control product, read that last phrase again and consider this story: Last summer, out of the blue, thousands of aphids appeared on my eggplants. Three days later, ladybeetles arrived and began eating the aphids and laying clusters of orange eggs on the undersides of leaves. As I anxiously waited for the eggs to hatch, I examined a few leaf samples with my 20x microscope. Two other beneficials — predatory mite larvae and syrphid fly larvae — had beaten the ladybeetles to the punch. Within a week, the aphids were gone. If I had sprayed those aphids with insecticidal soap, I would have wiped out the food supply for three major predators. It was a lesson I will not soon forget.

RSS | Comments | E-mail | Print