It’s maddening to spend weeks watering and weeding a garden bed only to have it decimated by insect pests. I refuse to use commercial pesticides, given the health risks they pose both to humans and to beneficial insects like bees. I prefer other methods for pest control and am always on the lookout for new strategies.
The first step is to pay attention. I walk my garden regularly, looking for signs of damage--wilted or spotted leaves, chewed leaves and stems, etc. — that way I spot some pest problems before they become overwhelming.
Some insects can be controlled by hand-picking. Many beetles and caterpillars are relatively large, slow, and easy to spot and grab. I patrol affected plants daily. I’ve been really surprised at what a difference this has made in keeping pest damage to a minimum.
I use several nontoxic substances that repel pests. I work wood ashes into the soil around my brassicas to ward off cabbage maggots and sprinkle coffee grounds around my eggplants to repel flea beetles. Most insects are reluctant to chew plant leaves that have been coated with diatomaceous earth, which is nontoxic but has to be reapplied after heavy rain.
Many pests have natural predators such as birds and bats. Houses for these garden friends invite them to come and feast. One year I noticed many potato beetle larvae being devoured by tiny insects which burrowed into their backs. It looked gross, but in the following year I didn’t have a potato beetle problem. Beneficial insects thrive in the absence of pesticides, and in the presence of host plants like herbs, alfalfa, daisies, Queen Anne’s lace, and buttercups. The flowers also add visual cheer to my garden.
Crop rotation helps to prevent pest infestations. So does good garden cleanup--either putting debris from affected plants through a hot compost pile or, in extreme cases, dumping it far from the garden.
See this Fact Sheet on Integrated Pest Management (IPM) from Ohio State for some great information, including a helpful table that shows which tactics are most effective against particular insects.