Tips For Getting Rid Of Hornworms

Anyone that has found hornworms in the garden knows they can literally destroy a plant in no time. These caterpillars can be a trifling nuisance for tomatoes, peppers, and some herbs. One hornworm can strip a plant of it’s leaves in just a few hours – they are eating machines. Because of their ferocious appetites, hornworms can grow to a large size in just a few days.

They can reach sizes of 6 inches long and almost an inch in diameter. Hornworms can be very difficult to prevent, but they can be slowed down. If you have found a hornworm munching on your precious vegetable plants, here are some tips for getting rid of these pesky critters:

One of the best practices is to check your plants daily (if possible) for any signs of hornworms. Don’t worry – you’ll notice if they are present very quickly. Check for any chewed leaves. Just the “meaty” parts of the leaves will be chewed off, the veins of the leaf will most likely still be present.

Obviously, check to see if you spot the caterpillars themselves. Hornworms can be tough to spot at first because they blend in very well with the plants. Make sure to look closely, and check under the bottom sides of leaves. Also, look on the ground and on leaves for any signs of hornworm droppings. It will be very noticeable for a large hornworm. It looks similar to tiny rabbit poo – small black or dark brown pellets.

Another way to spot them is to spray the plant with soapy water. The soapy water will cause the hornworms to wiggle and convulse around, making it easier to spot them.

If hornworms are found immediately remove them from the plant and either drop them in a container of soapy water or smoosh them. One thing to watch for when handling hornworms, when you grab them they will turn around and eject a dark brown or black liquid on your hand. It’s advised to use gloves or tweezers to pick them up with. Unless you want that goop on your hands.

You can use a mixture of garlic, insecticidal soap, and cayenne powder diluted with water to keep the sphinx or hawk moth out of your garden, and from laying eggs. This will help to control the hornworms from ever entering your garden. Put the mixture in a garden sprayer or a bottle sprayer that attaches to a water hose, and spray your plants. The moths hate the smell of the solution, and will not get near it.

Place a couple bird feeders around your garden in strategic locations. Some birds including robins and mocking birds can spot the worms and devour them for lunch.

You can also plant a big patch of dill on one end of your garden. Hornworms absolutely love dill, and might go for the dill plants instead of the tomatoes or peppers. Diversions are legal when fighting garden pests.

Public enemy number one for hornworms are the parasitic wasp. The parasitic wasp lay their eggs on the backs of hornworms, which the caterpillar will carry around until the eggs hatch. Once the wasp eggs hatch, they will kill the hornworm for food.

For more information about hornworms, please visit the Hornworms page.