Tomatoes can be plagued by a numerous insects.
Most will feed on the leaves, but some can climb up the vine, reach your fruit and chew holes in your tomatoes, preventing your crops from ripening.
To grow truly delicious ripe tomatoes, you need to know what’s eating holes in tomatoes to drink its juices.
Read on to discover the variety of nuisance insects that will forever plague your tomatoes and how to stop it.
What is eating holes in my tomatoes?
Snails and slugs make the biggest holes on tomato plants. Smaller holes can be caused by the tomato fruitworm, the hornworm or the tomato cutworm. The flea beetle tends to cause shotholes in the leaves, while the stink bug will pierce holes in the leaves, stem, and put pinprick holes in tomatoes.
The tomato fruit worm
The tomato fruit worm causes more damage to tomato crops than it does a single tomato.
Moths arrive and lay eggs on the leaves. When the eggs hatch, fruit worms are difficult to notice as they’re a light green color making them somewhat camouflaged by the greenery of the leaves.
Once the green fruits emerge, the fruitworms then pierce small holes in the green tomatoes, then move onto another, doing the same again.
A single larva can leave multiple small holes on numerous green tomatoes, preventing them from ripening.
When the larva is done feeding on ripening tomatoes, the worms drop off the plant, go into the soil and then by the summer, the pupae emerge as moths.
In their early stages, tomato fruitworms are green when they’re on the plant. They turn brown as they’re entering the pupae stage. Then a fortnight later, moths emerge from the soil and the cycle repeats.
The fruitworm is not the same as the tomato hornworm. A hornworm doesn’t leave holes in tomatoes. Instead, it feeds on the foliage, stripping tomato plants of all its leaves, then moving onto the fruit.
However, hornworms don’t leave holes in tomatoes. They cause scarring on the skins of tomatoes rendering them inedible.
Before it reaches that stage, you’ll can tell there’s a hornworm presence by the loss of foliage on tomato plants.
Hornworms can be picked off tomato plants.
For fruitworms, spray the plant with Bacillus thuringiensis (Bt), which is an effective insecticide that’s harmless to humans.
Slugs and snails
Slugs and snails leave large holes in tomatoes and on the plant’s foliage. Whilst they can climb up the vine, the damage is always more severe on the lowest part of the plant.
The tell-tale sign of slugs and snails feeding on your tomatoes is the trail of slime they leave behind.
The attraction for these garden pests is moist soil. These both prefer feeding at night, so watering early morning so the soil isn’t too moist overnight can help protect your tomatoes from an onslaught of these critters.
Sprinkling diatomaceous earth (De) around your plants can prevent slugs and snails from reaching them.
The sharpness of diatomaceous earth rips the skin of slugs and snails that cross them, causing them to dehydrate and die. Since they’re slow on the move, they’ll probably die before they reach your tomatoes.
A humane method for controlling slugs and snails is to relocate them to your compost bin where they can assist in gardening by helping organic matter decompose.
Stink bugs or shield bugs
Stink bugs are sometimes called shield bugs because they have a body the shape of a shield. The term “stink” is a reference to the stench they release if you crush them, so don’t do that.
The insect itself is six-legged with a mottled gray-to-brown color, a triangular-shaped body and is around three-quarters of an inch long with two antennas.
The adults have wings and are strong flyers. Nymphs are just as damaging to crops, but don’t have the same flight capabilities until they mature.
Their twin antennas are what pierce holes in the fruits of your tomato. The holes they make are only tiny pinprick sizes, just like a needle injection. That’s the stink bug making a hole to drink the juices from the tomato fruit.
Surrounding each prick in the skin of tomatoes will be discoloration. Where the juices have been sucked out the fruit, the skin will turn yellow.
The more stink bugs are present on your crops, the more pinpricks you’ll see and you’ll wind up with tomatoes with a mottled yellow skin that won’t ever fully ripen.
To prevent stink bugs from damaging your crops, they need removed at first sighting. You can either pick them off by hand, or regularly spray the plant with a jet stream of water to remove them.
As a natural deterrent, plant some trap plants such as marigolds or any that are yellow-colored as stink bugs are attracted to yellow flowers.
Planting flowers that produce pollen and nectar can help attract parasitic wasps, which use host feeding, meaning they lay their eggs inside the eggs of other insects.
Rather than more stink bugs emerging, the wasp kills the larva and uses the egg as a host for its own eggs.
Other insects that parasitic wasps help control the population of include: scale insects, caterpillars, beetles, and aphids.
Flea beetles feed on the leaves of plants leaving behind tiny shotholes. The most damage happens on young seedlings. Mature plants have large enough leaves to survive with a few holes in them.
The holes caused by flea beetles don’t extend to the fruit so these won’t leave holes in the tomatoes, only on the leaves. In sufficient numbers though, the damage can be intensive, which increases the risk of bacterial infections such as blight and wilt.
Infestations of flea beetles still need controlled for tomatoes to fully ripen.
Cutworms are caterpillars distinguished by others by their nighttime feeding habit.
During the day, these lay in wait in the soil. By night, they start to eat through the stems of tomato plants and can wriggle their way up to the fruit where they’ll pierce holes in your tomatoes.
There’s a few different types of cutworms differentiated only by color. The black cutworm, variegated cutworm and the spotted cutworm. Each eventually mature into moths and repeat the cycle again.
The difference between the cutworm, fruitworm and the tomato hornworm is that cutworms can be contained to the soil by placing a collar around young seedlings.
Tomato collars can be as simple as a round cutting of cardboard placed around the base of a stem. It prevents cutworms climbing up to reach your fruit.
Frequently Asked Questions related to what eats holes in tomatoes
What insect eats tomatoes from the inside out?
The tomato fruitworm eats its way into a tomato, then drains its juices from the inside. The fast decay of ripening tomatoes is a certain indicator of a fruitworm presence. In just a couple of days, fruitworms can turn nearly ripe tomatoes to mush.
What’s the best way to protect tomatoes from being eaten by critters?
Grow under a cloche, or in a greenhouse, and inspect your plants every day. If you grow tomatoes in the open, there will be insects attracted to them. You can’t eliminate them completely. All you can do is control them. Regularly hose the leaves, treat it with neem oil, or another natural insecticide, and handpick larger insects off.
Marcel runs the place around here. He has a deep passion for houseplants & gardening and is constantly on the lookout for yet another special plant to add to his arsenal of houseplants, succulents & cacti.
Marcel is also the founder of Iseli International Commerce, a sole proprietorship company that publishes a variety of websites and online magazines.