Gardening Tips: Your Tomatoes and The Dreaded Tobacco Hornworm!

When it comes to effective gardening, every little tip counts! Just when things are going great and your plants are doing well, something can go drastically wrong. Gardening is definitely trial and error, but with a little research, you can get ahead of the little problems and issues that arise while you’re enjoying this wonderful hobby.

As I was going through some old photos the other night, I came across some shots I got of a Tobacco Hornworm I had found in my garden some years back, covered in these little white Tic Tac shaped things. Those were no Tic Tacs, however, but PARASITIC WASP EGGS! Between the eggs, the horn and the eye patterns, the whole thing was an outright spectacle, as seen below!

That shot, though quite amateur in a lot of respects, is still one of my favorite photos I have ever taken simply because of the subject matter. This backyard phenomena makes the photo on its own! But while wonderful to photograph, there are some things you might want to know about the Tobacco Hornworm, the wasps, and the impacts on your garden and plants.

What is a Tobacco Hornworm?

The Tobacco Hornworm, actually a caterpillar, is found across North America, Central America and Australia, but is most prevalent in the Southern states of North America. Its most favorite snack are tobacco plants but they will settle for its cousin, your tomato plants (they also like other plants you grow). If you have ever gone into your garden mid-season and saw branches of your tomato plant missing, you might assume the deer are getting to your plants. While that is certainly possible, chances are better that you have yourself a Tobacco Hornworm problem. Left to their own devices, these caterpillars will truly decimate your crops!

The hornworms are decently big, sometimes growing to be larger than an adult male’s pinky finger and measuring up to roughly 3.9 inches. Living up to their namesake, they have a terrifying looking bright red horn at the end of their bodies. While daunting in appearance, the horn is not poisonous and just serves as a deterrent to predators. They have a very close relative, the Tomato Hornworm, who also wreaks havoc on your plants, but has slight differences in appearance…the biggest difference and easiest way to distinguish the two are their horns. The Tobacco Hornworm has a red horn whereas the Tomato Hornworm’s horn is black or dark blue.

Where do they come from? What is their life cycle?

Adult moths emerge from the soil and lay their eggs on a host plant, typically on the leaves towards the stem. This placement is safer from predators and has proven to provide better nutrients for the hatchlings. The caterpillars hatch from late spring to early summer. Once born, they are a problem for the home gardener and this is when you might start to notice your plants altered and eaten.

Once they have fully grown, they drop to the ground from their host plants and begin the pupation process and undergo their transformation into a moth. The moths, known as Manduca Sexta (seen above), or sometimes Carolina Sphinx moths, emerge to pollinate and lay eggs, some laying up to 1000 eggs alone. The lifespan of the moth stage is only a few weeks, making that some impressive productivity!

How do you deal with Tobacco Hornworms?

Pests such as the tomato hornworm are easy enough to deal with if you are diligent. A good gardener will seek out their eggs on their plants in early-mid spring. Check the surface of your leaves and stems for larger whitish-pale green eggs. You can simply(gently) remove them by hand or tweezer and destroy them. A little effort now goes a long way later, so pick a nice day to take your time and find as many as you can!

Of course, seeking out the eggs might not completely resolve the issue and a few might sneak by. While I am not much for killing anything needlessly, I am opposed to things that destroy my garden and thus make exceptions to this rule. Should you find a caterpillar, the best option is to kill it swiftly. Left to its own devices, it will destroy your tomato plants quickly and effectively. If you prefer not to kill them, another option is to take them and throw them in your neighbor’s garden. While fascinating to look at, they will absolutely make short work of your plants and should be dealt with accordingly.

What are parasitic wasp eggs?

One of the main predators of the the Tobacco or Tomato Hornworm are various types of parasitic wasps. The adult wasp will lay its eggs inside the caterpillar. The wasp larvae feed on the caterpillar’s internal tissue until they reach pupation, where they weave silk-like cocoons that protrude from the caterpillars body (what I previously referred to as Tic-Tacs.) Once they mature and leave their cocoons, the weakened caterpillar dies.

While they are terrifying in concept and seem like a problem, these parasitic wasps are actually a natural pesticide for these hornworms. In the instance you should find a hornworm riddled in wasp cocoons, leave it be and let nature run its course. Each cocoon will produce a female wasp and provide further defense against the Tobacco Hornworms in your life for generations to come.

Knowledge is Power!

In closure, if you take your gardening seriously and want to protect your plants as best as you can, take your time to study the Tobacco Hornworm and its eggs so that you can eliminate them before they hatch and defoliate (eat the leaves) of your treasured plants! A little knowledge and preparation can go a long way to having the best yields and healthiest garden you possibly can!

If you enjoyed this article and would like to get more garden tips as well as articles on music, technology, philosophy, life and more, be sure to subscribe to the Joy of Everything Blog. We do our very best to post only quality content, and your support is extremely meaningful to the future and success of this blog and Telford Moon as a whole!

Happy Gardening!