Insect control in herb gardens is a delicate process because the results must be safe to eat. Identifying the type of pest is the beginning of the process. Approach the problem from several angles, both removing the pests from the herb garden and working to get rid of the conditions that invited the problem insects in the first place.
Control insects by harboring a healthy soil environment that is less friendly to insect invaders. Conditions that can contribute to the development of an insect problem include poor drainage, underwatering and excess organic matter on the surface of the soil. Discarded matter like dead leaves or blooms can harbor an insect-friendly atmosphere. Types of pests that frequently attack herb gardens include aphids--green bugs that attach themselves to tender plants and leaves, often on the underside; fungus gnats--tiny fly-like bugs that thrive in too-wet soil atmosphere, wind up in your coffee and scatter when you water the plants; mealybugs, which stick to and suck on plant leaves; spider mites; and nematodes.
Mulching can help reduce insect pests in an herb garden. Reflective mulch controls the number of bugs in a garden, reducing the presence of insects by around 10 percent. Using cedar mulch in a garden can control insects by repelling them.
Insecticides can be used to control insects in an herb garden; however when working with indoor gardens, particularly edible herb gardens, a gardener must be conscious of the safety of the materials she is using for insect control. Because herbs are edible, precautions must be taken to keep pest control methods safe for human consumption. In addition to concerns about the herbs' food safety, an indoor gardener must be aware of the safety of any children or pets that come into contact with the herbal planting area.
Hands on Control
Many herb garden pests are best controlled by handpicking. Once you have put on protective gloves, anything you can catch that won't sting or poison you is fair game. Caterpillars, mealybugs, worms, aphids and beetles can be caught and disposed of to prevent them from reproducing and populating the garden.
The right kind of insect can be an asset to your garden by removing harmful insect pests. The ladybug or lady beetle, a well-known dark red beetle with black spots and a black head, eats the sucking aphids that attach themselves to your herb garden.