Asked on Sep 03, 2015

My tomato plants have 4 of these on them. WHAT in the world are they?

by Louise
Not sure how much definition you can see, but they're fat segmented green worm looking things with these small white things on top of them that look like small pieces of rice. I assume they might not be a productive thing for my plant? What do I do with them? I don't like to kill creatures.
  19 answers
  • Judy Judy on Sep 03, 2015
    They are tomato worms that will shred your tomato plant. The white rice looking items are eggs from a wasp that will eat the worms they hatch and grow. My suggestion is to handpick the worms all.
  • Sarah A. Victory Sarah A. Victory on Sep 04, 2015
    I saw my first Tomato worm in the last 5 yrs. At first I thought it was a tobacco worm as they look a lot alike. Pick them off and destroy them or you will have no greenery on your tomatoes.
  • Carol Claremont Carol Claremont on Sep 04, 2015
    Tomato Hornworms - pick them off and put them somewhere - I have woods so I put them on a tree or something - I have killed some in the past but I think they turn into butterflies or something so I don't anymore - they will eat up your tomato plants and sometimes they are hard to see but follow the path on the leaves that are gone and you might find others.
  • Mychelle primeau Mychelle primeau on Sep 04, 2015
    If you don't want to kill the worms get the hose and heavy sprinkler on them from close. But they will probably come back so keep a close eye on them.
  • Catherine Smith Catherine Smith on Sep 04, 2015
    Agree with everyone else. Those are tomato hornworms which will shred tomatoes, eggplant, potatoes, etc. Pick them off and dispose of them, UNLESS you want to do a nature lesson with kids. Pick off one or two along with a couple of stems and leaves from your tomato plant and put them in a glass container with air holes in the lid. You can watch them go thru their life cycle and turn into a 5 Spotted Hawkmoon Moth. Search the web for more info and pictures.
  • AdrianaG AdrianaG on Sep 04, 2015
    No, non, no! Do NOT kill the parasitised hornworms. The larvae will kill them for you and you will increase the population of beneficial a wasps. Only kill hornworms without the wasps,
  • Janet Pizaro Janet Pizaro on Sep 04, 2015
    agree with eveyone else tomato horn worms There are sprays and or tomato dust for the control.
  • Jeanie Smith Jeanie Smith on Sep 04, 2015
    These actially kill them off. Google it
  • Louise Louise on Sep 04, 2015
    agree with AdrianaG leave the tomato hornworm alone. they are beyond beneficial to the enviroment. parasitic wasps seek them out to lay eggs on them,and this paralyzes the worm and the worm will eventually die. the parasitic wasps are as good for the enviroment as the bees are and we all know bees are at a premium because of pesticides. once the eggs are on the worms you could pick them off your plants and put them somewhere else but they are harmless.
  • JoAnn JoAnn on Sep 04, 2015
    Not tomato hornworms. A good thing. Always glad to see them because I know I won't have tomato hornworms. They are eggs for a type of wasp that kills the worms.
  • Patty S Patty S on Sep 04, 2015
    The hornworm is the larvae of the butterflies. I control them by planting Marigolds in my tomato garden , one near each plant. The butterflies do not like marigolds and will not lay their eggs on your tomato plants. I have never had a hornworm since I started doing this.
  • Wilda Campton Wilda Campton on Sep 04, 2015
    sprinkle with floor. I did once.
  • Jill Jill on Sep 04, 2015
    Oh, I so wish I had them here. This last summer was bad. This summer was just as bad with the tomato hornworms here. One decimated tomato plant, all the leaves gone, and the tomatoes destroyed. But it didn't stop there. I have been constantly dealing with them and my brussel sprouts. Apparently, they like them too. Marigolds and all kind of bug resistant plants did no good. But, a little Dawn dish soap in a sprayer has kept them at bay and we might actually have brussel sprouts this year.
  • Louise Louise on Sep 04, 2015
    If they can be mailed without killing them, I'd do it.
  • LILLIAN LILLIAN on Sep 04, 2015
    I thought they where mealybugs. Ive never heard of hornworms nor do they have them listed in Sunset?
  • AdrianaG AdrianaG on Sep 05, 2015
    For treating hornworms and other caterpillars, other than puling them off and squashing them, get Safer Garden Dust. At the first sign, sprinkle the plants. Home Depot carries it online. It is a safe organic treatment for all kinds of caterpillars. You need to have it on hand ahead of time, because by the time you order it and get it delivered the damage will be done.
    • See 2 previous
    • Jill Jill on Sep 07, 2015
      @Adriana, last year I rebuilt my raised garden beds. I sifted all the soil going back into them to remove all the grubs, rocks and other things. The screen was really fine, so they surely couldn't have come in the soil. We do have a lot of months in the last year or so, that I have noticed, but they are just plain white moths. None that look like the moths from the hornworms in the video. The only place I can think they came from is in the soil with the plants themselves. I live in Southern CA, where rain is a rarity in the last few years for everyone. We are in one of the severest droughts ever, so reapplying the dust isn't going to be a issue all the time because of rain.
  • Anne Anne on Sep 05, 2015
    The caterpillars are tomato hornworms. They're beautiful creatures. The 'white grains of rice' looking things are the eggs of parasitic wasps, which, as they hatch, will consume the worm from the inside out. (What a horrible way to go!) Hornworms (if not attacked by the wasps and not killed with Sevin dust or other pesticide) will turn into beautiful Sphinx moths (AKA hawk moth or hummingbird moth), usually 4" to 6" in size. If you can spare a few plants, then let the worms munch as much foliage as they can. Check out this video from YouTube:
  • Annie Medic Annie Medic on Sep 09, 2015
    Tomato hornworms with wasp eggs on it. Natural predation in affect. The horn worms are voracious tomato plant destroyers, the wasps keep them in check.