Tomato Hornworms can ruin your tomato plants overnight. Here's how to get rid of tomato hornworms. If you notice the leaves of your tomato plant have been chewed to the stalk, and it looks like the plant has been stripped of it's leaves, you have a tomato hornworm infestation.
Nothing like coming up to the house to find large portions of your tomato plants stripped of their leaves. This is what happened to us, so we made a video about the tomato hornworms who took over our tomato patch.
The Tomato Hornworm is the caterpillar of the Five Spotted Hawk Moth, a relatively non-descript moth, but in its caterpillar stage wreaks havoc on tomatoes.
In the video I talk about the eggs of the parastic wasp, then I realized later the white protrusions from the caterpillar are the cocoons of the braconid wasp, not its eggs, which is even better, as soon they will hatch and parasitize more Hornworms. If you want the whole insect story, check out the Tomato Hornworm page at Wikipedia.
I have heard about cardboard collars one can put around a young tomato plant to prevent the Hornworms from crawling up the stem. Another way, according to Wikipedia, to reduce the resident population is to roto-till the garden, as this will destroy hornworm pupae in the soil.
If you see a wild sounding moth-bug think flying chaotically around your garden, it could be the adult moth of the tomato hornworm. I have only seen the moth a few times, but its huge and looks like a crazy bug thing.
We have a number of how to grow tomatoes and how to cook tomato videos on our site here. I especially like our cherry tomato recipes, one of them is a raw cherry tomato pasta dish that is brilliantly simple.
Roast Cherry Tomato Pasta Recipe Video
Fresh Cherry Tomato Pasta Recipe Video
Get Rid of Tomato Hornworms Video
Hamilton
On the premise that an ounce of prevention is worth a pound of cure, I did a bit of googling around. This one guy somewhat vaguely says on the Organic Gardening Forum at http://forums2.gardenweb.com/forums/load/organic/msg0210594620482.html that "I pinch the first or second leaf stem just hard enough to bruise it which causes the plant to produce an enzyme that is LETHAL to Hornworms. I have used this tech for 10 years and have not had one hornworm make it to adulthood." PNAS (Proceedings of the National Academy of Sciences of the US) has an article at http://www.pnas.org/cgi/content/full/102/52/19237 that elaborates. Any mechanical damage or herbivory (chewing upon) induces tomatoes to produce "proteinase inhibitors (PIs), which are expressed rapidly and systemically in response to wounding."
The short version is, in response to localized damage a whole tomato will plant will interfere with mr. hornworm's metabolism and he'll die. Yay!
If it doesn't work, as a backup try delivering the chemical to the hornworm via a tea spray... of tomato plant tea. My mother says she recalls Crockett, the Victory Garden guy, saying that if you clip off hornworm-chewed stems and make a tea, and spray that on the tomatos, that it will kill off the worms.
Amanda
We have found Thuricide to be an effective remedy when we found a solitary Hornworm starting the defoliation process on our tomato plants. Thuricide is a natural and organic alternative to chemical pesticides. It's a liquid formulation of the bacteria Bacillus Thuringiensis (Bt), which is an organism that effectively kills leaf eating caterpillars including loopers, cabbage worms, tomato horn worms, leaf rollers, gypsy moths and many others.
Cathy Fullinwider
In reference to removing and killing hornworms,why not let them provide some good use by feeding them to the birds. I pull them off,drop them in a bucket of water,no stabbing needed,come back laterr that day,then place cut segments on my bird feeders. The birds have a tasty dinner,& the ones I laid out on tree branches were snapped up,one by one of those spiny lizards,fun to watch.
J.E. Young
Why are tomato hornworms usually found at the top of the plants when there are bigger vines and tomatoes nearer the bottom. Does this mean they do not crawl up from ground but are initially deposited nearer top of plant?