Ways to get rid of caterpillars include picking them up and disposing of them, cutting off damaged parts of plants in the garden, planting flowers that attract parasitic wasps and spraying bacillus thuringiensis on plants. Caterpillars that eat plants containing alkaloids may be resistant against parasitic wasps and other parasites.
Individuals who don't like the idea of picking caterpillars up and killing them forcefully may be more comfortable picking them up with gloves and tossing them into a bucket of soapy water to get rid of them. After repeating this process for a week, there's a good chance that all of the caterpillars have been eliminated. A gardener should continue to check for signs of caterpillars and their eggs after disposing of visible pests.
An individual who doesn't want his plants to sustain too much damage from cutting and burning the damaged parts of the plants may want to cut the plants early in the planting season so that the plant can recover and grow again. Examples of flowers that attract parasitic wasps include parsley, dill, fennel and other umbelliferous flowers. Parasitic wasps plant their eggs inside of caterpillars, which eventually kills them when the eggs hatch.
Bacillus thuringiensis kills all types of caterpillars. The downside to this is that there are some caterpillar species that are not harmful.