
Tomato hornworms are a common pest that can wreak havoc on your tomato plants.
These large green caterpillars can quickly strip your plants of their leaves and fruit, leaving them weakened and vulnerable to disease.
Fortunately, there are several effective methods for getting rid of tomato hornworms.
One of the most effective ways to control tomato hornworms is to physically remove them from your plants. This can be done by handpicking them off your plants and dropping them into a bucket of soapy water to kill them.
Another effective method is to use natural predators like parasitic wasps, which lay their eggs on the hornworms and eventually kill them.
There are also several organic and chemical methods for controlling tomato hornworms.
These include using neem oil, which can be sprayed on your plants to kill the hornworms, as well as using insecticidal soap or Bacillus thuringiensis (BT), which is a natural bacteria that kills the hornworms but is safe for other beneficial insects.
In this article, we'll cover
1. Identifying Tomato Hornworms

What Are Hornworms?
Tomato hornworms are large, green caterpillars that can grow up to 4 inches long. They are commonly found in gardens and can cause significant damage to tomato plants.
These pests are often mistaken for tobacco hornworms, which look very similar but have a few key differences.
Signs of Tomato Hornworm Infestation
The most obvious sign of a tomato hornworm infestation is the presence of large, chewed holes in the leaves of tomato plants.
As the infestation progresses, the caterpillars may also begin to eat the fruit of the plant. In addition to the damage they cause, tomato hornworms also leave behind dark green droppings on the leaves and stems of the plant.
Tomato vs. Tobacco Hornworms
While tomato and tobacco hornworms look very similar, there are a few key differences that can help you identify which pest is affecting your garden.
Tomato hornworms have black spots on their body, while tobacco hornworms have white stripes. Additionally, tomato hornworms have a curved horn on their rear end, while tobacco hornworms have a straight horn.
If you suspect that you have a hornworm infestation in your garden, it’s important to act quickly to prevent further damage to your plants. The next section will cover some effective methods for getting rid of these pests.
2. What Causes Tomato Hornworms?

Tomato hornworms are one of the most destructive pests that can attack tomato plants.
These large, green caterpillars can quickly strip a tomato plant of its leaves, leaving it weak and vulnerable to other pests and diseases. But what causes tomato hornworms to appear in the first place?
One of the main causes of tomato hornworms is the presence of adult moths in the garden.
These moths lay their eggs on the leaves of tomato plants, and when the eggs hatch, the larvae emerge and begin feeding on the leaves and stems of the plant.
Adult moths are attracted to tomato plants that are already stressed or weakened, so it’s important to keep your plants healthy and well-fed to prevent infestations.
Another cause of tomato hornworms is poor garden hygiene. If you leave dead plant debris on the ground or don’t clean up fallen fruit, you’re providing a breeding ground for pests like tomato hornworms.
These pests can overwinter in the debris and emerge in the spring to attack your plants. Be sure to clean up your garden at the end of each season to prevent this from happening.
3. Preventing Tomato Hornworm Infestations

Cultural Control Methods
Cultural control methods involve altering the environment to prevent or reduce the occurrence of tomato hornworms.
- Till soil at the beginning and end of each gardening season to destroy overwintering larvae. Tillage has shown to cause up to 90% mortality.
- Rotate crops to prevent the buildup of hornworm populations in the soil.
- Remove plant debris and weeds, as they provide shelter for hornworms.
- Plant tomatoes in areas with plenty of sunlight and good air circulation to discourage hornworms.
Biological Control Methods
Biological control methods involve using natural predators or parasites to control tomato hornworm populations.
- Encourage the presence of parasitic wasps, which lay their eggs on hornworms. The wasp larvae then feed on the hornworms, killing them.
- Attract beneficial insects like ladybugs and lacewings, which feed on hornworm eggs and larvae. Planting sweet alyssum, butterfly weed, garlic, marigolds, calendula, queen anne’s lace, parsley, cilantro, or dill can help attract these insects to your garden.
Chemical Control Methods
Chemical control methods involve using pesticides to kill tomato hornworms. However, these methods should be used as a last resort, as they can harm beneficial insects and other wildlife.
Pesticide | Active Ingredient | Effectiveness |
---|---|---|
Bt (Bacillus thuringiensis) | Bt toxin | High |
Neem oil | Azadirachtin | Medium |
Spinosad | Spinosyn | Medium |
Bt is a natural bacteria that produces a toxin that is lethal to hornworms. Neem oil and spinosad are derived from plants and are considered organic pesticides.
When using pesticides, always follow the instructions on the label and wear protective clothing and equipment.
4. Removing Tomato Hornworms by Hand

One of the most effective ways to get rid of tomato hornworms is to remove them by hand.
While it may seem like a daunting task, it can actually be quite satisfying to see the results of your efforts.
The best time to search for tomato hornworms is early in the morning or late in the evening when they are most active. Look for their telltale signs, such as droppings and damaged leaves, to locate them.
Once you have found a hornworm, simply pick it off the plant and drop it into a bucket of soapy water to kill it.
If you have a large infestation, consider enlisting the help of friends or family members to make the task more manageable.
Alternatively, you can offer a small reward to children or neighbors for each hornworm they find and remove.
Be sure to check your plants regularly for new hornworms, as they can quickly multiply and cause significant damage.
By staying vigilant and removing them by hand, you can effectively control the population and protect your tomato plants.
5. Using Natural Remedies to Get Rid of Tomato Hornworms

There are several natural remedies that you can use to get rid of tomato hornworms. These remedies are safe and effective, and they won’t harm beneficial insects or the environment.
Here are some of the most popular natural remedies:
- Handpicking: One of the easiest and most effective ways to get rid of tomato hornworms is to pick them off your plants by hand. Wear gloves to protect your hands from the hornworms’ spines, and drop them into a bucket of soapy water to kill them.
- Diatomaceous earth: Diatomaceous earth is a natural powder that is made from the fossilized remains of diatoms. Sprinkle it on your plants and the soil around them to kill tomato hornworms and other pests. The powder is abrasive and damages the hornworms’ exoskeleton, causing them to dehydrate and die.
- Neem oil: Neem oil is a natural insecticide that is derived from the neem tree. It works by disrupting the hormones of the tomato hornworms, preventing them from feeding and reproducing. Spray it on your plants to kill the hornworms and deter other pests.
Remember to always follow the instructions on the product label when using natural remedies, and test them on a small area of your plants before applying them to the entire plant.
Also, keep in mind that natural remedies may take longer to work than chemical pesticides, so be patient and persistent in your efforts to get rid of tomato hornworms.
Conclusion
Tomato hornworms can be a frustrating pest for gardeners, but there are several effective methods for getting rid of them.
By understanding their lifecycle and habits, you can choose the best approach for your garden. Here are some key takeaways:
- Tilling soil at the beginning and end of each gardening season can help destroy overwintering larvae and reduce the hornworm population.
- Encouraging beneficial insects like wasps can act as a natural biological control for hornworms.
- Handpicking and removing hornworms from plants is a simple and effective method, especially for smaller gardens.
- Natural repellants like neem oil and cayenne pepper can be used to kill and deter hornworms, but be careful not to harm beneficial insects.
- Chemical insecticides should be used as a last resort and with caution, as they can harm beneficial insects and other wildlife.
With these methods in mind, you can take control of your garden and prevent tomato hornworms from causing damage to your plants. By staying vigilant and implementing preventative measures, you can enjoy a healthy and thriving garden all season long.