Tomato worms (also known as hornworms) can be as rampant in your garden as the plague during the hot weather You’ll know you’ve got them on your tomatoes, eggplant, peppers, and potato plants if you notice withered and chewed leaves, droppings, or green worms on your plants. Knowing techniques for how to get rid of tomato hornworms will be one of your best defenses in your garden.
You may feel like all hope is lost if you find that your plants have a tomato worms infestation, but that’s simply not true at all. You may find yourself running for the pesticides if you see that your plants’ stems are stripped clean of their leaves, but not to worry. There are definitely ways to keep their population at bay, if not avoid them all together if you are diligent.
Some people turn to organic pesticides to keep the population under control, and if you feel like time is slim, that may be the way you want to go. The organic pesticide that you would use for a hornworm infestation is bacillus thuringiensis (BT). Because I am an organic gardener and tend toward avoiding pesticides of any kind, I’m going to share with you how to get rid of tomato hornworms in your garden without them.
Before I get to the how-to, let me give you some of my best tips to head any pests off at the pass before you need a pest-control plan.
Tomato worms are probably the one pest that most vegetable gardeners know of because they are huge, green, and ugly! They start off as tiny little worms and can grow to be around 3 inches long and about as fat as the base of your pinky finger!
Did you know that there are actually two different but very similar varieties of these pests? They are tomato worms and tobacco hornworm. The difference is in the markings and the moth they come from, but that doesn’t matter, really. They essentially do the same thing--devour your plants, and they can do it overnight if the infestation is particularly bad.
Their lifecycle is as follows: moths lay eggs on the undersides of leaves in the late spring, which hatch within a week. Next, the caterpillar larvae will feed on your plants for the next 4-6 weeks. Once that part of the cycle is over, the hornworm will create a cocoon for itself in order to overwinter in your soil. Moths then emerge in the spring and will begin the cycle once again. In warmer climates, this life cycle may take more than once per year.
Tomato worms aren’t very easy to find, especially if they are just hatched. New larvae are very small, but you can still tell it’s a hornworm by the “horn” on the back end of it. If you see small whitish eggs that look like tiny grapes on your leaves, that could be hornworm eggs and those will need to be removed.
The more likely indicators you’ll see are missing leaves, chewed stems, and dark green (almost black) droppings. If you see droppings on a leaf or on the ground, check the underside of whatever leaves are above that spot. Examine your plants often, especially during hot weather. Ladybugs, wasps, lacewings, and yellow jackets feed off the small larvae of the plants, but if you observe the kind of damage I described earlier, there are probably larger ones on your plant.
Chemical-free treatment: When you find a hornworm, pick it off your tomato plant. If you are squeamish and don’t want to touch them, just break the leaf stem off and throw them in a bucket, or if you have chickens, let them fight over these tasty morsels. If you don’t have chickens to bless with these grubs, make sure to remove them from your yard by dumping them in the trash. It usually takes about 2 weeks of daily “hunting” to get them all and save your plants, but if you are diligent every day to look your plants over, you can avoid losing plants in their entirety.
Organic pesticide treatment: Follow directions found on your bottle of BT (bacillus thuringiensis). You can get this at any local garden center.
There are a few ways to keep tomato worms even more at bay than with the tricks I’ve shared with you, and they are pretty easy if you know what to do. First, you can make sure to till the ground at the beginning and end of any season, which will disrupt the life cycle of the soon-emerging hornworm moths in the spring. This would be especially important to do if you had a previous hornworm infestation in the bed in question. Second, you can interplant dill, basil, or marigolds with your plants to keep pests at bay. And lastly, keep your wasps around, as they are a natural predator to the hornworm.
Kristi Stone is a student of all things modern homesteading, and is living the dream on her 1 acre hobby farm. Her favorite things to do include growing and preserving food for her family, breeding and raising Nigerian Dwarf goats, studying and using herbs, and running her hobby farm in sunny Southern California. Kristi writes about all of these topics and more on her blog, Stone Family Farmstead.