Tomato Pest Control: Natural and Organic Options

by on March 21, 2012

We get a lot of questions about urban garden pest control and today we wanted to share some good info on some of the insects that threaten the beloved tomato plant.

hornwormTomato Hornworms

The tomato hornworm (Manduca quinquemaculata) is an ugly beast. One look at them and you will easily see where they got their name thanks to the prominent horn that makes them look far more intimidating than they really are. The hornworm quickly defoliates the top of a tomato plant but they are often difficult to spot because their coloring allows them to blend easily with the plants they eat. They are also more likely to be found feasting on the underside the plant during the heat of day, preferring to come to the outer leaves only around dusk.

Hornworm Treatment

The most common way to eradicate the tomato hornworm is by picking off the offenders as they appear. To avoid them before they become a problem, rototilling the soil after the season ends will expose and destroy the pupae before they become a problem. A respectable level of preventative biological control has been realized with the use of Bacillus thuringensis or BT (soon to be available in the UrbanFig Shop)


Aphids are tiny little weapons of mass destruction that literally such the juices out of your tomato plants. As if that wasn’t bad enough, they can often infect the plants with diseases they pick up along the way. Sounds like common street trash you’d see on COPS, doesn’t it?

Aphid Treatment

Aphids can be treated in several ways. Biologically, ladybugs and lacewings, along with some species of bird are known predators, and introducing ladybugs to your garden will almost certainly end your aphid infestation. Culturally, you can hose aphids from infested plants, trim away badly damaged areas and spray your tomato plants with non-toxic insecticidal soap. Neem oil has also been shown effective in the eradication of some species of aphid, though not all.

{ 25 comments… read them below or add one }

Beth Jones March 21, 2012 at 5:10 PM

I have a tremendous ladybug presence in my yard. Makes me super happy! Hornworms tho have been a problem in the past. I have learned what they look like and last year made a fairly good attempt at keeping them off my plants by hand.


Michael Nolan March 21, 2012 at 5:15 PM

I had a lot of hornworms last year and they made life rather difficult for a while but we won in the end.


nicole Maynard March 22, 2012 at 8:57 PM

Did you know that Hornworms make a terrible sound when you pull them off the plant. They seriously give me the heeby jeebies !!! I have been using BT I am seriously hoping I won’t have to encounter these demon worms !!


Michael Nolan March 23, 2012 at 8:05 AM

Hrm. I don’t remember a sound!


Sheila Weiss January 11, 2014 at 3:34 PM

BT kills ALL caterpillars. That means no butterflies in your yard. It’s a big price to pay!


Carol January 11, 2014 at 4:14 PM

We recommend that gardeners use as little organic pesticides as possible, but with an infestation it is very helpful to use BT. The caterpillars will find their way back eventually if BT not overused.


Susie April 17, 2014 at 10:06 AM

They are so yicky! I use a pair of scissors to cut them in half right off the plant. They are really gooey but the scissor wrath keeps the screaming down ;D


Kaluska Poventud April 3, 2012 at 9:20 AM

Would Neem Oil work on fungi on my Plum tree leaves?
Just planted a plum tree a few months ago and the leaves have theses little and in come cases not so little holes !! thank you !


Michael Nolan April 3, 2012 at 4:09 PM

I would definitely give Neem oil a try before anything else.


Marj August 12, 2012 at 5:34 PM

The easiest way to find the nasty tomato hornworm is to go out in the morning when it’s quiet, shake each plant, they make a snapping noise to try and scare off predators, then snip them in half with scissors and leave them to die, I grew up on a tomato farm, I speak from experience.


Larry January 11, 2013 at 4:43 PM

We always have the braconid wasp in our garden, and they take care of the tomato hornworm without us getting involved. They young braconid wasps hatch out after digesting the original worm and multiply by laying eggs in other worms. if you see back of the hornworm covered with white cocoons of the braconid wasp, leave the hornworm alone so the cocoons will mature and hatch out to infect other hornworms. If you destroy a hornworm with those cocoons on it, you will destroy a lot of beneficial insects.


Wendy January 11, 2013 at 4:55 PM

A little birdseed kept birds landing on my tomato cages on their way to the seeds. They noticed the worms too and gobbled them up!


Harriette Jensen January 11, 2013 at 5:21 PM

Hornworms bring out the killer instinct in me. I once had a horde of them on my plants. I dug a hole, picked the buggers off the plants, dumped them in the hole, put a shovel of dirt over them, and stamped and stamped on the dirt until they were all good and dead!


Judith January 22, 2013 at 4:54 AM

Last year I did have a few but the cardinals were quite fond of them, and I saw them visit often. I repeatedly tied up my fines to expose the inside areas of the plants, that grew quite tall. I lost only a few tomatoes and was happy to help Mrs. Cardinal find juicy food for her babies. I can’t kill the worms. I am far too soft hearted. I prefer to let nature do it.


Ryan April 25, 2013 at 7:30 AM

Conserve Naturalite works fast on caterpillars and it’s a natural product. Spinosad is the active ingredient. I’ve used BT in the past but found it to be to slow for my liking.

Neem is a good natural pesticide but it must be used at first sign of insects because it works as a growth regulator of sorts to stop insect from molting properly to go along with its stop feeding mechanism. Neem oil doesn’t suffocate insects the way horticulture oil does. Thats often a mistaken mechanism of Neem


Laura June 6, 2013 at 8:06 AM

I won’t touch the worms. I just clip off the part of the branch where the hornworm is sitting, and lay it in the driveway. Eventually one of our hungry birds will see it and take it away!


chem dry September 29, 2014 at 9:11 PM

Howdy! This is my first comment here so I just wanted to give a quick shout out and say I truly enjoy reading through your articles.
Can you suggest any other blogs/websites/forums that deal with the same subjects?
Appreciate it!


Maxine Akilah Woodward April 10, 2015 at 6:28 PM

I need a organic treatment for hornworms.


Carol April 14, 2015 at 6:25 PM
Diane September 29, 2015 at 1:31 AM

pest control for tomatoes


Doug December 1, 2015 at 8:25 AM

Hornworms cannot tolerate marigolds. Plant them next to tomato plants. It works!


Donna June 17, 2016 at 8:29 PM

I’ve planted a lot of tomatos in my time, I’m near 80 and this Screaming sound…hmmmmmsomebody is pulling somebody’s leg me thinks..


Judi June 27, 2016 at 3:08 PM



Eileen July 21, 2016 at 4:11 PM

Please consider NOT killing the hornworms on your tomato plants. Yes, they eat some leaves but not the whole plant. (In my experience) They turn into a beautiful hawk moth if you let them live!


Carol July 21, 2016 at 5:58 PM

Interesting point 🙂 I imagine they are beautiful.


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