Big, fat, and green! Here are tips on how to identify, control, and get rid of tomato hornworms in your garden.
What Are Hornworms?
If you’ve ever grown tomatoes, chances are good that you’ve dealt with these green caterpillar pests. There are two main garden pest species, tomato hornworms and tobacco hornworms, which can be found in most regions of the U.S. and in southern Canada. Both species can ruin your tomato crop in record time! They also feed on other plants in the Solanaceae (nightshade) family: eggplants, peppers, tobacco, and potatoes. They blend in quite easily with the green foliage and feed non-stop, creating spotty and chewed leaves and fruit.
Tomato (and tobacco) hornworms live according to the following life cycle:
- In late spring, large adult moths lay eggs on the undersides of foliage, which will hatch within a week. The adult moths are easily recognizable; they’re commonly called sphinx or hummingbird moths.
- Caterpillar larvae will hatch in late spring and feed for 4–6 weeks before creating a cocoon, overwintering in their pupal state in the soil. If the weather is warm enough, larvae may only burrow for as little as 2–3 weeks.
- Moths will emerge in the spring, and will then lay eggs once again. More than one generation a year may be possible in warmer climates.
Tomato hornworm moth (female). Look out for the moths in late spring. Photo by Didier Descouens/Wikimedia Commons.
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Horn Worms
I used to experience horn worms but one year I saw the white cocoons on the back. The horn worm had quit eating and soon became dessicated. The horn worm wasp emerged and propagated and I never again had a problem with the horn worm. That was the year I planted golden rod and saw so many tiny insects on it and do believe it attracted the wasp.
Tomato Horn Worms
Tomato and Tobacco Horn Worms make great fish bait. Just place their heads on the pointy end of the fishhook and turn the wrong side out. Bream, Crappie, and Bass love them and it's a good way to get rid of them while catching fish for dinner.
Tomato hornworm?
I'm a long time gardener, and have picked plenty of these guys off tomatoes in July or August, but I'm stumped. Today we found a huge one that had eaten nearly all the leaves off two small perennial geranium plants I was getting ready to plant in my garden. I've never seen them this early before, or eating plants other than tomatoes. Has anyone else had this happen to them? Quite a curiosity for me.
geranium devourer
This is news. Mind you, we would never second-guess a long-time gardener who knows his hornworms but…could it have been a cabbage looper? These small green critters do eat geraniums; we can’t find evidence of hornworms consuming them. Can anybody comment further??
tomato hornworm
I live in western North Carolina and I picked 4 off of my tomatoes this week. I planted this tomatoes in pots from last year so i don't know if there were eggs in the soil from last year. They sure are destructive.
Tomatoe Hornworm
My mother-in-law Mary Joe Taylor taught me this -
When you plant the seeds or the young plants put a Large WHITE Styrofoam or Paper cup with the bottom cut out in the hole so that it is up about 4" out of the ground and put the plant in the cup. Make sure you have at least 4" above ground level of the white cup. These worms are like crickets "They won't cross white" ! Make sure that NONE of the limbs on your tomato plant touch the soil as the worms will cheat and use those leaves to climb up to the plant and then your efforts are for naught. I think that trick with the WHITE cup works on other plants as well as other pest like maybe the cutworm. Try it - I haven't had cutworms in years since using this trick!
white cup defense
Thank you, Nancy, on behalf of tomato lovers everywhere!
Where the Hornworm eggs are
This is my 4th year growing tomatoes. Tomato Hornworms are a problem every year. I am determined to be their nemesis. We use tomato cages and the moths often lay their eggs on leaves near the metal of the cage. I suppose they use the cage for support sometimes. The moths can be largish and the metal of the cages offers more support than tomato leaves. The eggs are usually on the underside of the leaves, but not always. So looking for eggs near the cage metal can be quite productive. Rolling eggs off of a leaf is usually fairly easy and considerably less gross than dealing with the hornworms. Of course, the moths lay elsewhere, so keep an eye out for telltale damage. Cheers!
Hornworms
Do you step on them?
I pay for worms
I pay for the worms. Reptiles love them!!
JUST GROW TOMATOES
You should just grow some tomato plants in the summer and collect the worms. Then you could keep the worms alive until your reptiles have eaten them all. Just get the ones you grow in a container. I am sure it has to be cheaper than buying them all the time. It is just a thought.
what to do with hornworms
You can step on them, Ken, but that would make a mess. Drowning in a bucket of water is easier. Then discard them.
Step on Horn worms
Crushed them with your boot heal. Messy but effective, also gets your anger out for the damage they do!
Has anybody tried netting?
I plant tomatoes in large containers on my back deck, and will try netting over each plant to hopefully protect the moths from laying their eggs in the soil. The fact that The Green Menace lays eggs twice a year doesn't help matters. I'll give a heads up if it works.
Netting
I just ordered mosquito netting to try. Hope that works but guess they may already be in the earth just waiting
Attacking my Jalafuego pepper plant
I've noticed this is the first year I've had THWs got them 3 times now on a new jalafuego plant almost destroyed it, grew back just found number 2,3,4. #2 was about an inch long maybe 3mm thick other 2 were fresh hatched worms clear and tinyyy. I can't till because my bell pepper plant is 5 years old and is huge and would love to not destroy it. Anyway add any pepper plant to plants they attack, not just bells sadly :/
We pay for worms
Hi everyone! We pay for those green worms. Our reptiles love them!!
companion plants
I have basil, marigolds, and dill planted amongst my tomato plants in my raised bed...still got a hornworm. :(
Not Just Tomatoes
These devils bypassed my tomatoes and ate my potatoes down to the ground, then infested my datura plants. As these are night-blooming flowers, I am not entirely surprised, but pulling them off by hand is harder than you would think. Those suckers are STRONG. I have a small garden, so hand-picking works well, but planting dill only ended up feeding the grasshoppers. Did nothing to deter hornworms.
it's my first year gardening in Alabama after 20 years in Colorado. Takes some time to identify indigenous pests. A bunch of worms the size and thickness of my middle finger springing up out of nowhere? Didn't expect that.
hornworm problem
As I got older I started container gardening in one side of my driveway figuring it would be easier and less pest. Little did I know
these monster hornworms where more at my door step than I thought.They are a real wrestler when it comes to hand removal
so I now use needle- nose pliers to remove .Four Oxheart tomato plants this summer and removed ten of these rascals.
Horn Worms & holes in my tomatoes
I just went out and checked my 4 pots with tomatoes planted in them. I found a bunch of horn worms and actually one big brown worm that looked similar to a horn worm except for color. I picked off the worms I found and pulled them in half and threw them away but I also found that a lot of my tomatoes had holes in them and many of the holes were very discolored. I cut into one tomato expecting to find a worn or something but there was nothing there. Can you tell me what might have caused these holes in my tomatoes?
Hornworms
I bought a blacklight flashlight and go out after dark to look for hornworm. They glow really bright against a black light.
blacklight flashlight
Thank you! Didn't know about the black light! I will give that a try.
Hornworms Tobacco Worms Black Light
Black light at night is terrific. Got 144 worms last year (approx 16 tomato plants). Also look for miniscule green balls on leaves. Kill them all.
Horn Worms
I'm surprised this article did put the best and easiest way to keep horn worms from eating your garden.. Which is planting onions in between your plants whatever they are.... It always works every time....
tomato hornworms and onions
question - if onions work (planting them between tomato plants) to repel hornworms - what about leeks? would they work also? This year I have lovely container tomatoes and SO FAR no worms - I'd like to keep it that way!
Tomatoes
What do you think of DE for the pests?
Diatomaceous Earth
Diatomaceous earth (DE) does work against hornworms, though you should only use it when the plant is NOT in bloom. DE will kill pollinators, so avoid using it on or around flowers.
My chickens love them
A time consumer finding them and picking them off my tomato plants, but a tasty treat apparently for my chickens.
Dawn & water solution.
After picking off what worms i could find i sprayed a solution of dawn & water on my tomato plant leaves. Now the leaves are turning brown & the whole plant is looking poorly. Also what blooms there were are falling off. I thought this was supposed to be a safe way to rid the plants of worms. I think i have lost all my tomato plants. Any ideas??
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