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Tomato Hornworms: How to Identify, Control, and Prevent Them

Image Credit:
Amanda Hill
Written By: Catherine Boeckmann Executive Digital Editor and Master Gardener

Big, green, and hungry—tomato hornworms can wipe out your tomato crop almost overnight. These giant caterpillars love to feast on tomato leaves and fruit, and they won’t stop there. Peppers, eggplants, and potatoes are also on their menu.

”This one is nobody’s friend if you’re a gardener and like to grow tomatoes,” says entomologist Jeff Smith, curator of the Bohart Museum of Entomology’s Lepidoptera collection.

The good news is that these pests are easy to spot once you know what to look for, and they can be controlled without resorting to harsh chemicals. In this guide, learn how to identify tomato hornworms, understand their life cycle, and discover effective natural ways to get rid of them—plus tips to keep them from coming back next year.

🐛 Hornworms munching your tomatoes? Our Almanac Garden Club members get exclusive pest guides, expert webinars, and practical tips to protect their crops. Protect Your Garden Now.

What Are Tomato Hornworms?

If you’ve ever walked out to your tomato plants and found bare stems where lush foliage used to be, chances are hornworms were at work.

  • The tomato hornworm (Manduca quinquemaculata) and the closely related tobacco hornworm (Manduca sexta) are garden pests found throughout most of the U.S. and southern Canada.
  • Both species feed on plants in the nightshade family (Solanaceae): tomatoes, eggplants, peppers, tobacco, and potatoes.
  • Because of their size and appetite, a small number of hornworms can defoliate plants quickly.

These pests are the larval stage of large night-flying moths (sphinx or hawk moths).

Tomato Hornworm crawling on a tomato vine.
Tomato troublemaker in action—meet the tomato hornworm! Photo by Amanda Hill.

Identification

How to Identify Tomato Hornworms

Look for big, green worms on tomato plants! Hornworms are some of the largest caterpillars in the garden. Key features include:

  • Color: Pale green with V-shaped white markings along the body
  • Horn: Dark, pointed “horn” protruding from the rear
  • Camouflage: Blends almost perfectly with tomato leaves, making them tricky to spot
  • Size: Can reach up to 4–5 inches in length

Tip: Inspect your tomato plants daily. Check the undersides of leaves for eggs and watch for early signs of feeding damage.

Tomato Hornworm vs. Tobacco Hornworm

Both species damage tomato plants, but here’s how to tell them apart:

  • Tomato hornworm: White V-shaped markings; black horn
  • Tobacco hornworm: Diagonal white stripes with black spots; red horn
tobacco hornworm
Can you tell which hornworm this is? 
(It’s a tobacco hornworm! Notice the white stripes with dotted black lines and a red “horn.”) 

Signs of Tomato Hornworm Damage

  • Chewed or missing leaves, often starting at the top of the plant
  • Wilted stems and bare stalks
  • Dark green droppings (frass) on leaves or soil
  • Chewed fruit and sunscald on tomatoes (caused by loss of leaf cover)

Tomato Hornworm Life Cycle

Understanding the life cycle helps you prevent infestations:

  1. Eggs: Laid on undersides of leaves in late spring; hatch within 1 week
  2. Larvae (hornworms): Feed heavily for 3–4 weeks
  3. Pupae: Burrow into soil to overwinter in a cocoon
  4. Adult moths: Five-spotted hawk moths emerge in spring to repeat the cycle

In warmer regions, there may be two generations per year.

Tomato hornworm moth (female)
Tomato hornworm moth (female). Look out for the moths in late spring. Photo by Didier Descouens/Wikimedia Commons.

Control and Prevention

How to Get Rid of Tomato Hornworms

1. Handpicking

  • The most effective method for small gardens:
  • Check plants daily and remove caterpillars by hand
  • Drop them in soapy water, or feed them to backyard chickens

2. Use Organic Controls

  • Bacillus thuringiensis (Bt): A safe, natural bacterium that kills young caterpillars (must be ingested).
  • Neem oil or insecticidal soap: Can work on small caterpillars, but less effective on large hornworms

3. Encourage Natural Predators

  • Parasitic wasps lay eggs on hornworms (you may see white cocoons attached)
  • Ladybugs, green lacewings, and birds also feed on eggs and larvae

If you find a hornworm covered with white cocoons, leave it—the wasps will do the control work for you

A tobacco hornworm covered with parasitic wasp eggs.
Nature’s drama! A tobacco hornworm becomes a nursery for parasitic wasps.

How to Prevent Hornworm Infestations

  • Till soil in fall or spring to destroy overwintering pupae (up to 90% mortality)
  • Rotate crops—avoid planting tomatoes in the same spot year after year
  • Use companion planting: Interplant dill or basil to deter pests; plant marigolds at borders
  • Attract  beneficial insects  by planting nectar-rich flowers

Frequently Asked Questions

Do tomato hornworms bite?
No. They look intimidating, but they cannot sting or bite humans.

What does a tomato hornworm turn into?
A large five-spotted hawk moth, also called a sphinx or hummingbird moth.

When do tomato hornworms appear?
Eggs are laid in late spring, and larvae are most destructive from June through August.

Can tomato hornworms eat other plants?
Yes. They also feed on peppers, potatoes, eggplants, and tobacco.

More Help for Gardeners: See our Garden Pest and Disease Library for tips on other common problems.

Do you have tomato hornworms? How do you handle them in the garden?

Garden Pests

About The Author

Catherine Boeckmann

Catherine Boeckmann

Executive Digital Editor and Master Gardener

Catherine Boeckmann loves nature, stargazing, and gardening so it’s not surprising that she and The Old Farmer’s Almanac found each other. She leads digital content for the Almanac website, and is also a certified master gardener in the state of Indiana.

Read more from Catherine Boeckmann

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Comments

<span>John</span> Mon, 07/10/2017 - 17:20
My grandmother used to go out in the evenings or early mornings with a pair of scissors and just snip in half every hornworm she found - never had to touch them.
<span>Lesley Hanking</span> Mon, 07/10/2017 - 13:53
I noticed a lot of black dropping on the ground around my cherry tomato plants about 1 month ago they looked like coffee grounds because we had some gusty winds the night before I thought that they had blown off the roof and as I was sweeping them away I notice a large green caterpillar I googled it and discovered it was a tobacco hornworm so I went over all my plants and removed over 20 all varies sizes then I got my husband to check over them behind me and discovered a few more that I missed. The next morning there were more droppings and I removed another 10 and for the next 3 mornings after more droppings but only 3 this time then 1. Then nothing I thought I was in the clear then just last week I found a huge amount of dropping around by Better boys and discovered the biggest fattest hornworm yet. This is the 1st year I've seen them do you think I will get them every year now? I forgot to mention that all my Tomatoes are in containers on my deck with fresh soil every year.
<a title="View user profile." href="/author/editors">The Editors</a> Tue, 07/11/2017 - 15:54

Hi Lesley,

The tomato hornworm pupates into a sphinx moth, also known as a hawk moth. They lay eggs on tomato plants that will turn into the hornworms. Since you change your soil every year, it is unlikely that they will be a consistent problem year to year: No pupas will overwinter in your soil. The moths are just finding your plants. Keep in mind, right now is prime moth season. As summer moves on into August, you will see less sign of caterpillars and moths.

 <span>Nancy Taylor</span> Sun, 07/16/2017 - 11:59
Years ago, cutworms would devour my tomato plants just before I could harvest tomatoes until my mother-in-law passed along some tried and true Wisdom to me. When you plant your tomato plants take a "WHITE" Styrofoam cup size Large, cut the bottom out of it, place it in the hole and put your tomato sprout in it, be sure to leave the cup up out of the ground most of the way (use just enough dirt to hold it around the plant). As your tomato plant grows make sure that you prune any stems that can touch the soil which are usually the first stems so the worms cannot crawl up the stems that they can reach from the ground outside the cup. The white cup acts like a barrier to keep the cutworms off the plant, this is the same reason that crickets are kept in white Styrofoam bait boxes, cutworms & hornworms like crickets will not pass over WHITE - True story, I never have had a problem since nor has anyone I have shared this knowledge with - Blessings from Mary Joe Green Taylor !
<span>Richard</span> Thu, 07/06/2017 - 17:58
I just put a UV blacklight flashlight on my list for purchase. Really appreciate that info. I'm not sure I want to see all the other stuff it can reveal though! Also the info about leaving the ones that have the wasp larvae on them is interesting. Did this article really tell us they dont cause any more damage to the plant once they are studded with these little white things? I take great pleasure in chopping these things right in half, right on the stem they are on with my Fiskar pruning shears when I find them...like killing an alien life form when their green slime is spilled. I am so mad at them for robbing me of the produce my plants would have provided, I wish I could do worse to them. Also, when they are killed and left behind, especially the parts that fall off the plant to the ground (some parts stay clung on and shrivel right there), the rest of nature loves to eat them. I saw little yellow bees just gobbling the carcasses up and of course the ants and all love them.
<a title="View user profile." href="/author/editors">The Editors</a> Fri, 07/07/2017 - 10:23

Your assertion is correct: infected hornworms will continue to feed until they are killed by the parasitic wasp larvae. If you want to ensure that there will be no further damage, you can remove the infected hornworm and place it far away from your garden. This way, the caterpillar won't damage your crops, but the wasps will still be able to emerge and attack more hornworms.

 <span>Jeffrey Burd</span> Tue, 07/04/2017 - 19:01
Worm / Caterpillar on Morning Glory plant and we have several other butterfly plants there but also used to have some tomatoes.
<span>Jeffrey Burd</span> Tue, 07/04/2017 - 18:59
Can I leave a picture to know if this is a GIANT Swallow tail OR a Tomato Horn worm
<span>Donna Hayhurst</span> Mon, 06/19/2017 - 09:24
Are Horn Worms the only GREEN worms to be found on tomatoes. I found 3 smallish green inch worms on my plants this morning, no horns I could see but many holes in leaves and one good size stem almost completely severed in half. Maybe they are baby Horn Worms?
<span>John Pastirchak</span> Sat, 06/24/2017 - 12:52
What remedy do you suggest for those smaller green worms found imbedded in the tomato fruit itself? Finding limp, mushy green tomatoes with worms busily devouring the fruit though no sightings on the limbs or leaves. Oddly, it's random-- surrounding tomatoes seem both uninhabited and healthy. So far, no sightings of the larger horn worm.