Spray them with Bt.

Some people recommend the Chemical ( SEVEN ) but picking them off is the most effective method, if you won’t or cant do that. Get a can of Cigarette lighter fluid, spritz a bit on the worm and light it, just don’t go crazy with the fluid a small amount will do just fine,

then what’s the problem?…. picking them off is the one true organic way to be rid of them… and it works, too!…. the only other ‘organic’ method uses Bt, bacillus thuringensis, the disease that kills caterpillars of many species…. good and bad…..

put your gloves on and go get ‘em…. drop them into a jar of soapy water…. when you have them all, put the lid on the jar and leave it overnight…. empty it the next day when you go back to check for more cats…. there will be more as later-laid eggs hatch….don’t be squeamish…. they’re actually kinda cute when you look at them closely and watch their movements….. just don’t fall in love….

if you don’t want to kill them, leave one tomato plant just for them…. they turn into those amazing hummingbird moths …..

Use an organic compound that consist entirely of a natural occurring pathogen found in nature. It is called Bacillus Thuracide.

An agriculture student at Oregon State University conducting an experiment noted some of the caterpillars he had captured as specimens died for no known reason. He researched it and found they died of a disease that only caterpillars can catch, and best was it is present in nature on it’s own, a natural disease like a cold or flue in humans.

The student isolated the pathogen and cultivated it and found it is effective as a natural control for cabbage caterpillars, tomato horn worms, corn silk worms and many others.

You can purchase BT at any garden store in a powder or liquid form. It is very cheap and once you get the pathogen started in your garden, your garden will be Tomato Horn Worm and cabbage worm and corn silk worm free zone in the future.

Now I wish someone would come up with a study on some pathogen that affects snails and slugs in my garden.

You know the best and most effective way to rid yourself of these pest without using insecticides
BT will kill them but it is slow acting and the worm will continue to damage your tomato’s while the BT works to kill them.

Bt is effective when they are small but not on the big ones. there is a parasitic wasp that lays eggs in the hornworm and it is quickly consumed by the wasp larva from the inside out. If you see a hornworm with what looks like grains of rice all over its’ back it has been parasitized by these wasps and soon enough most of the hornworms in your garden will be too. So if you see a hornworm with rice on it leave it alone.

Otherwise hand picking is the best option. Do this early in the morning and around sunset when the critters are active.