Tomato Pests: All You Need to Know for a Healthy Garden

Growing your own tomatoes can be a rewarding experience, but it’s also important to be aware of the potential pests that can make it challenging. In this article, we’ll address the most common tomato pests and provide valuable information on how to identify, prevent, and manage them to ensure a bountiful harvest.

Tomato pests come in various shapes and sizes, but don’t worry, we’re here to help you tackle these invaders head-on. From tiny insects to voracious caterpillars, knowing their characteristics and behaviors will empower you to protect your tomato plants effectively and maintain a healthy garden.

With the right knowledge and tools, you can minimize the damage done by these pests and enjoy the fruits of your labor. Stay tuned as we dive deeper into the world of tomato pests and share all you need to know to keep your garden thriving.

Understanding Tomato Pests

Tomato plants are attractive to various pests. Understanding these common tomato pests, such as the tomato hornworm and tomato fruitworm, is essential to ensure your plants stay healthy and productive.

The tomato hornworm is a large green caterpillar that feeds on the leaves and occasionally the fruit of tomato plants. They are prevalent in North America and can be identified by their horn-like projection at the rear end. To manage tomato hornworms, you can handpick and remove them from your plants or use biological control agents like parasitic wasps source.

The tomato fruitworm is another destructive pest that affects tomato plants. This caterpillar, which can be found in various regions of North America, tunnels into the fruit and leaves, causing significant damage. To control tomato fruitworms, maintain good garden hygiene and consider using chemical or biological methods, such as the use of microbial insecticides source.

Here is a brief comparison of these two pests:

Tomato Hornworm Tomato Fruitworm
Large green caterpillar Smaller, pale green to brown caterpillar
Feeds on leaves and sometimes fruit Tunnels into fruit and leaves
Mostly found on upper parts of the plants Can be found throughout the plant
Handpick or use parasitic wasps for control Use good garden hygiene and microbial insecticides for control

Some additional tips for managing tomato pests include:

  • Regularly scouting your plants for signs of damage or infestation
  • Encouraging beneficial insects, like ladybugs and lacewings, to help control pests
  • Practicing proper watering techniques, such as watering in the morning and using drip irrigation systems
  • Providing adequate space between plants for better air circulation source.

By understanding and addressing these common tomato pests, you can protect your plants and enjoy a bountiful harvest.

Types of Tomato Pests

Insect Pests

There are various insects that can infest your tomato plants and cause damage. A few common ones include:

  • Aphids: Small, sap-sucking insects that can cause leaves to curl and stunt plant growth.
  • Flea Beetles: Tiny insects that chew small holes in leaves, reducing the plant’s ability to photosynthesize.
  • Whiteflies: Small, white insects that can transmit diseases and cause leaves to yellow and die.

Regularly check your tomato plants for signs of infestation, and if needed, use appropriate control methods, such as insecticides or natural predators.

Nematode Pests

Nematodes, especially root-knot nematodes, can also cause issues for tomato plants. These microscopic worms attack the roots, leading to:

  • Stunted growth
  • Yellowing leaves
  • Reduced fruit production

To manage nematodes, you may need to use nematicides or practice crop rotation.

Mollusk Pests

Mollusks like slugs and snails can be a problem for tomato plants, as they feed on tender leaves and fruit. To minimize damage, consider:

  • Removing hiding places (like debris) near your plants
  • Using barriers (such as copper tape or diatomaceous earth)
  • Setting traps

In summary, regularly monitor your tomato plants for potential pests, take appropriate control actions when necessary, and keep your garden clean to minimize the chance of infestations.

Identifying Tomato Pests

Tomato pests can cause various issues in your garden, and being able to identify them is crucial for healthy plants. In this section, we’ll focus on a few common pests and their symptoms, to help you take appropriate action if needed.

One common pest found on tomatoes is the tomato hornworm. You might notice large holes in leaves, or even fruit damage. Caterpillars blend in with the leaves, making them difficult to see. To spot them, look for their black or dark green droppings on the leaves.

Another issue tomatoes face is insects causing yellowing. Nutrient deficiencies, insects, or diseases may be responsible. To identify the exact cause, it’s important to examine their symptoms. Insect infestations typically cause irregular patterns of yellowing, whereas nutrient deficiencies cause a more uniform yellowing.

Webbing on your tomato plants could indicate the presence of spider mites. To confirm their presence, hold a white piece of paper under a leaf and gently shake it. If you see small, reddish mites falling onto the paper, then spider mites are there. These tiny pests can cause leaf damage, yellowing, and even distortion in severe cases.

Identifying pests early is essential for effective treatment. Consider using the techniques we’ve provided to ensure healthy tomato plants in your garden. Regular monitoring, combined with appropriate prevention and treatment methods, will help protect your tomatoes from harmful pests.

Methods of Prevention and Control

Natural Pest Control

To prevent and manage tomato pests, you can integrate some beneficial insects into your garden. These predatory insects like lady beetles will help to destroy harmful pests. Another natural method is companion planting, which increases biodiversity in your garden. Some companion plants can be used as a trap crop which attracts pests away from your tomato plants. Examples of such plants include:

  • Radish
  • Marigolds
  • Eggplant
  • Potatoes
  • Peppers

On the other hand, some companion plants like garlic, basil, and mint can help to repel pests. To further reduce the risk of pests, consider practicing crop rotation on a regular basis.

Homemade Treatments

There are a variety of homemade treatments you can use to manage pests. Some examples are:

  • Homemade bug spray: Make a solution using water, dish soap, and vegetable oil
  • Insecticidal soap: Mix water, dish soap, and baking soda to create an effective spray
  • Neem oil: Dilute neem oil with water for a natural pesticide

Utilizing aluminum foil around the base of your plants can deter pests. Additionally, you can create cardboard collars to protect young plants from pests that crawl on the ground.

Chemical Pest Control

For more serious infestations, you may need to use chemical pest control methods. Some options include:

  • Insecticides: Effective in managing various pests, but may harm beneficial insects as well
  • Spinosad: A natural product derived from bacteria that is toxic to many pests, but safe for beneficial insects
  • Horticultural oils: Effective against soft-bodied insects like aphids, and safe for most plants
  • Bacillus thuringiensis: A naturally occurring bacterium that is toxic to certain pests but harmless to humans and beneficial insects

Remember to follow the label instructions carefully, and always consider using natural methods first to keep your garden healthy and eco-friendly.

Tomato Varieties and Growing Conditions

Choosing the right tomato varieties and understanding the best growing conditions can make a world of difference in your garden. Tomatoes come in many types, from the classic beefsteak to small cherry tomatoes, and each one has its own unique growing requirements.

Tomatoes thrive in a home garden environment, where you can carefully monitor their climate conditions. Start by selecting the best spot in your yard. Ideally, you want a sunny area exposed to morning sun, as this helps prevent the development of diseases and pests.

Here are some popular tomato varieties:

  • Beefsteak tomatoes: large fruits with thick flesh, great for slicing and sandwiches
  • Cherry tomatoes: small, bite-sized tomatoes that come with a burst of flavor
  • Heirloom tomatoes: unique varieties with special flavors

Dealing with Pest Related Diseases

Tomato plants can experience a variety of pest-related diseases, including fungal diseases and infestations from different pests such as tomato fruit worms, leaf miners, stalk borers, and sap-sucking insects.

Fungal diseases often thrive in humid conditions and can lead to issues like spotted leaves, which can result in poor fruit flavor and color. To prevent this, make sure your plants have adequate spacing for air circulation and avoid over-watering or using overhead irrigation systems. Also, remove infected plant debris and consider using fungicides if necessary.

Tomato fruit worms are caterpillars that can damage both the leaves and fruits of your tomato plants. When dealing with these pests:

  • Routinely check your plants for caterpillars and remove them manually
  • Use well-timed insecticides to manage heavy infestations
  • Encourage natural predators, such as birds and beneficial insects

Leaf miners are small insects that create tunnels in tomato leaves, affecting their ability to photosynthesize. To combat this problem:

  • Encourage beneficial insects that prey on leaf miners
  • Keep your garden clean and free from fallen leaves or debris

Stalk borers are caterpillars that tunnel into tomato stems, potentially causing wilting or even plant death. You can manage these pests by:

  • Hand-picking the pests from your plants
  • Maintaining proper plant-spacing to discourage their movement from one plant to another

Sap-sucking insects, such as aphids and whiteflies, can damage your tomato plants by feeding on the sap and excreting a sticky substance called honeydew. This can lead to the growth of sooty mold, which reduces your plants’ ability to photosynthesize. To manage these pests:

  • Introduce beneficial insects like ladybugs and lacewings to your garden
  • Use mild insecticidal soap or horticultural oil to control their population if needed
  • Prune and dispose of heavily-infested plant parts

By being proactive and surveilling your tomato plants regularly, you can mitigate pest-related diseases and maintain a healthy, vibrant garden.

Advanced Techniques for Pest Management

Using Row Covers and Traps

To keep your tomato plants pest-free, try using row covers and traps. Row covers, especially floating ones, are helpful in preventing pests like the Colorado potato beetle. They provide a barrier between the pests and your plants. For example, you can place a row cover over your plants early in the season before pests appear. Traps, on the other hand, help you monitor and reduce pest populations. For example, monitoring traps can help you detect the presence of pests, while sticky traps capture and reduce their numbers.

Staking and Weeding

Proper staking and weeding practices can contribute to healthier tomato plants and fewer pests. When staking your tomato plants, you provide better air circulation, which helps keep the plants dry and less hospitable for pests. Additionally, regularly removing weeds and applying mulch helps limit places for pests to hide, lay eggs, and reproduce. Examples of effective mulches include straw and black plastic.

Transplanting and Quick Removal

Finally, consider transplanting your tomato plants and acting quickly to remove infected plants. By transplanting seedlings instead of directly sowing seeds into the ground, you can potentially avoid soilborne pests. When you spot a pest problem, it’s crucial to remove the affected plants or parts promptly. This quick removal can help prevent the spread of pests to the rest of your garden. Don’t forget to dispose of the infected plants properly, preferably far away from your garden, as pests may still survive in the discarded plant material.

Reader Emails

Over the years, our website, whatsthatbug.com has received hundreds of letters and some interesting images asking us about these insects. Scroll down to have a look at some of them.

Letter 1 – Tomato moth cocoon?

 

Hi. Digging in the dirt where I usually plant my tomato plant, I discovered a cocoon the size of my thumb. It is brown and like I said, it is the size of my thumb. Any ideas what it may be? I put it in a jar with some of the dirt from where I was digging. I hope it will live. I can send a picture If will help you identify it.
Thanks
Michelle


Dear Michelle,
Did it have what looks like the handle on a jug? If so, it is the pupa of a Tobacco Hornworm Moth (Manduca sexta) which in its larval, caterpillar form is the dreaded Tomato Hornworm, a four inch long behemoth that devours the leaves of tomato plants, sometimes leaving them defoliated. The larva eventually buries itself in the dirt to pupate without spinning a cocoon, leaving its bare pupa to mature. The handle of the jug is actually the place where the long proboscus, a tubelike mouth that the moth uses to gather nectar from deep throated flowers. We would love a photo.

Hi Daniel. Thanks for getting back to me. I have attached a photo, but I’m afraid it’s not a very good one. It sounds like your know your bugs. My next question is, how do I get this thing to hatch? Is the moth beautiful? I would imagine that it is. I currently have it in some soil in a jar without a lid. Should I keep it out side or in the house? Let me know.
Thanks
Michelle

 

Dear Michelle,
The moth is large and mottled grey with very elongated wings. There are a series of yellow spots along the body. They are very strong fliers. While not traditionally beautiful, they are truly awesome. They are very similar to the moth used in the “Silence of the Lambs” advertisements, and you can also see a swarm of them crawling on Patsi Kensit (spelling?) in the totally awesome movie” Angels and Insects”. You are doing the right thing as far as getting the pupa to metamorphose. Do not let the soil either dry out or get too wet. Keep it out of the direct sunlight.

Thanks again for your time and the information. I hope I get to see him. I think I forgot to ask if you know how long it could take? Do you know?
Michelle

Dear Michelle,
Normally they overwinter as pupa and then metamorphose in the spring. I’m guessing your specimen has passed the necessary time underground and it should be happening soon.
Good luck.

Letter 2 – Tomato Bugs

 

I have grown tomatoes for many, many years and this is a first for me. I have enclosed a picture. Can you identify the larva/pupa? that is building the cocoon on my tomato? Good bug – bad bug? Thanks so much for your help.
Pat in Ida

Dear Pat,
That is one beautiful tomato. The caterpillar might be an Omnivorous Looper, Sabulodes aegrotata which matures into a medium sized rather pretty moth, however they are still garden pests. They defoliate my mint plants every year and also eat the leaves from my roses. As their name implies, they eat most any plant. They are very abundant in city gardens. During the day, the caterpillar hides in a loose webby shelter that they spin in a leaf fold, or between leaves, or in your case, on a ripe tomato. They will probably not chew the tomatoes, just the leaves.

Letter 3 – Tomato Bugs

 

Hi,
Recently we have found about 6 of the very large tomato hornworms(?) on our 2 tomato plants. They look very similar to the black and white photo on your website. Half of them had white oval fuzzy pieces all over the outside of their bodies. What are those? Eggs? We took them off the plant by either breaking the stems they were on or by picking them off with a Popsicle stick. They are eating our plants down to the stalks!
Thanks,
Rebecca

Dear Rebecca,
Those “eggs” you saw were in fact the cocoons of a parasitic Braconid wasp which was devouring the tomato hornworm alive. Nature’s own pesticide.

Letter 4 – Tomato Bugs

 

Hello,
I was wondering if you could identify this bug on my tomato plant for me…THANKS
Colloquially known as the “tomato bug”, the tomato hornworm is the caterpillar of the Tobacco Sphinx, Manduca sexta or Manduca quinquemaculata, large night flying moths.

Authors

  • Daniel Marlos

    Bugman aka Daniel Marlos has been identifying bugs since 1999. whatsthatbug.com is his passion project and it has helped millions of readers identify the bug that has been bugging them for over two decades. You can reach out to him through our Contact Page.

  • Piyushi Dhir

    Piyushi is a nature lover, blogger and traveler at heart. She lives in beautiful Canada with her family. Piyushi is an animal lover and loves to write about all creatures.

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