Tomato pest - Ask Extension
I'm providing pictures of a problem I had in 2025 with my tomatoes. I did not see any bugs or rodents in the garden. However in my endeavor to trouble...
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Tomato pest #925425
Asked March 04, 2026, 3:03 PM EST
I'm providing pictures of a problem I had in 2025 with my tomatoes. I did not see any bugs or rodents in the garden. However in my endeavor to troubleshoot, i did put a couple sticky traps under a couple tomato plants and did catch a couple female Cardinals.
As you can see even the green tomatoes have marks that look to me like their being scratched by a rodent or pecked by a bird. The red tomatoes show near symmetrical holes in them. My garden is fenced tight enough to keep out rabbits and deer. This is the first year I ever had this problem and the garden has been in the same spot for 15 years. I plant both determinate and indeterminant varieties , water and fertilize only from the bottom. I have many more pictures.
Dubuque County Iowa
Expert Response
There are several potential causes of damage like this on a tomato.
Based on what I can see in the photos, it is likely caused by birds and/or rodents such as mice, ground squirrels, or squirrels.
The best way to prevent bird damage is to cover the plants with netting.
Rodents are a little more difficult to manage, as they can more easily slip under netting and fencing, such as hardware cloth, that you place over the plant. You can use spray deterrents, but those that taste bad, like garlic spray or cayenne pepper, may be problematic for the edible fruit. Scent deterrents may be successful, especially when applied to a small perimeter around the plants.
Apply any repellent without directly applying it to the fruit. Frequent reapplication and a rotation between a couple of different scents will be needed to keep this management technique effective. This article discusses using repellents for deer, and the same advice would apply for rodents: https://yardandgarden.extension.iastate.edu/how-to/how-protect-gardens-deer#repellents
In most cases, when you see rodents or birds feeding on tomato fruit, it is because they are looking for water, which the fruit has in abundance. Sometimes, providing a nearby, easy-to-access water source will draw thirsty critters away from your plants, reducing or eliminating this damage.
Occasionally, damage from tomato fruitworm (aka corn earworm) can look similar to this, but there is typically more extensive damage inside and you would likely come across the caterpillar at some point during the summer. Learn more here: https://yardandgarden.extension.iastate.edu/encyclopedia/tomato-fruitworm
Additionally, many other insects and diseases can cause holes and decay on tomatoes, but this damage does not resemble damage from those types of pests.
--Aaron
Based on what I can see in the photos, it is likely caused by birds and/or rodents such as mice, ground squirrels, or squirrels.
The best way to prevent bird damage is to cover the plants with netting.
Rodents are a little more difficult to manage, as they can more easily slip under netting and fencing, such as hardware cloth, that you place over the plant. You can use spray deterrents, but those that taste bad, like garlic spray or cayenne pepper, may be problematic for the edible fruit. Scent deterrents may be successful, especially when applied to a small perimeter around the plants.
Apply any repellent without directly applying it to the fruit. Frequent reapplication and a rotation between a couple of different scents will be needed to keep this management technique effective. This article discusses using repellents for deer, and the same advice would apply for rodents: https://yardandgarden.extension.iastate.edu/how-to/how-protect-gardens-deer#repellents
In most cases, when you see rodents or birds feeding on tomato fruit, it is because they are looking for water, which the fruit has in abundance. Sometimes, providing a nearby, easy-to-access water source will draw thirsty critters away from your plants, reducing or eliminating this damage.
Occasionally, damage from tomato fruitworm (aka corn earworm) can look similar to this, but there is typically more extensive damage inside and you would likely come across the caterpillar at some point during the summer. Learn more here: https://yardandgarden.extension.iastate.edu/encyclopedia/tomato-fruitworm
Additionally, many other insects and diseases can cause holes and decay on tomatoes, but this damage does not resemble damage from those types of pests.
--Aaron
