Few things are as rewarding as growing your own veggies. All that careful gardening and all those days of waiting for your plant to bloom more than pay off when you see results in the form of fresh, vibrant produce that adds an extra-special flavor (metaphorically and otherwise!) to your plate of food.
Tomatoes, especially, make a great choice as they’re easy and quick to grow, highly productive, and of course, extremely delicious!
So imagine how disappointing it can be to have your tomato’s life cut short. All that effort and you literally cannot enjoy the fruits of your own labor.
Unfortunately, when trying to grow your own tomatoes (or any other vegetable, for that matter), pests are an all too common problem. These uninvited guests, with a tendency to overstay their welcome, can wreak havoc on your precious plants, especially in organic gardens.
Keeping these off is a battle that gardeners of all levels and types are constantly engaged in. This can be frustrating, especially for gardening beginners.
To help you in your gardening journey, here’s a list of the most common pests that enjoy your precious love apples as much as you, how to identify them, and how to repel them.
Most Common Tomato Bugs
Tomatoes, regardless of the variety, attract more than their fair share of pests. Here’s how to identify the most common.
1. Colorado Potato Beetles
Don’t let the name throw you off – these beetles love tomatoes just as much as they love potato tops. They’re also great fans of eggplants, peppers, and other members of the nightshade family.
These commonly found beetles are often mistaken for a strange variety of ladybugs since they look highly similar to the latter. However, their shells feature alternating black and yellow stripes, typically numbering ten, together.
Though the beetles are harmful enough, their larvae are even more damaging to your tomato plant. Colorado potato beetle larvae eat up all parts of the leaf except for the petioles and veins. They’re often difficult to spot; the weird leaf-eating pattern may be the only indicator of the larvae’s presence.
Preventing/Treating Colorado Potato Beetle Infestations
Here’s how you can prevent and treat Colorado potato beetle infestations:
- The key to protecting your tomato plant against these pests is to catch them early since your tomato plant will recover from a 30-50% loss of foliage; anything more will result in severe stunting.
- While adult beetles can be picked off by hand (make sure you use gloves) and exterminated in soapy water, there’s no way other than trimming off leaves to protect your plant against the larvae.
- Another thing to note is that Colorado potato beetles spend their winters in the soil, so avoid planting anything from the nightshade family in a spot that was previously infested.
- Growing “trap crops” and non-host plants in the garden, such as potatoes and corn, respectively, can also distract these pests and keep them away from the tomatoes.
2. Flea Beetles
While flea beetles won’t kill your precious tomatoes, they will definitely cause a deterioration in their health and spread quickly from plant to plant, eating up the fruit and leaving holes in the leaves as they go.
Named for its flea-like appearance and flea-like jumping abilities, the flea beetle is minute (around a tenth of an inch), with a jet black body that may feature yellow or white stripes.
Adult flea beetles feast on the foliage of the plant (they’re not picky eaters and will eat any Solanaceae plant) while the larvae feast on the plant’s roots.
Preventing/Treating Flea Beetle Infestations
Flea-beetle damage can be quite easily controlled unless the infestation is very severe. Some measures you can use to prevent infestations:
- Dusting diatomaceous earth on the soil around your plant (though you should be careful with the use of the substance as it is an indiscriminate killer that can kill pollinators, too).
- Sticky traps are a safer option. These capture jumping adult flea beetles and also give you an estimate of how severe the infestation is.
- Herbs such as basil and plants such as catnip, radish, and nasturtium may also help repel these beetles by acting as trap crops.
- Row covers are also helpful, as it is usually the younger plants that are susceptible to these pests.
- If the infestation is severe, powerful insecticides, like pyrethrin, can be applied.
- Beneficial nematodes can act as the front line of defense in the soil, directly attaching the pests by feeding on the larvae and pupae.
Flea beetles overwinter in the soil, so make sure you clear away any debris and till the soil. Crop rotation is also a good idea.
3. Aphids
The stuff of nightmares for gardeners of all levels. These pests are extremely destructive. Aphids probably the most common tomato pest.
Aphids can be pink, brown, black, or white, with pear-shaped bodies. These invaders settle on the underside of new leaves and on new stems, sucking the sap and leaving behind a sticky, fungus-like growth (honeydew) that is both a reminder of the destruction they’ve caused and an invitation for other pests.
From eggplant to potatoes, aphids attack a wide range of vegetable plants and usually settle in clusters.
Aphids are only considered a serious threat when the infestation is severe. However, small infestations shouldn’t be dismissed as they could balloon into a severe infestation very quickly, ultimately killing the plant.
Preventing/Treating Aphid Infestations
Some ways to treat aphid infestations:
- Aphids can be picked off by hand or simply wiped off the plant.
- Soapy water (normal or insecticidal soap), sprayed using a spray bottle, can suffocate the bugs and kill them.
- Spray bottles will also help forcefully remove aphids from the plant.
- If the infestation is severe, prune affected parts of the plant. Make sure you discard these in the garbage bin and not on the ground, as the aphids could easily migrate to nearby plants.
- Trap crops such as nasturtiums can distract aphids while also attracting aphid predators such as hoverflies and ladybugs.
- Horticultural and neem oil make the plant slick, making it hard for aphids to get a grasp on the leaf and stem surface.
4. Cutworms
Cutworms are moth caterpillars that reside in the soil and are easily distinguished by yellow or black spots on a brown or grey body. These worms can grow up to two inches in length.
Cutworms can make short work of tomato plants, destroying full plants overnight by leaving large holes in the fruit and leaves and attacking the stems so that the plants collapse. These caterpillars especially love seedlings.
Cutworms work at night and during the day, reside in the soil. There are several varieties of cutworms, such as common, black, turnip, greasy, and tobacco cutworms.
Preventing/Treating Cutworm Infestations
Some ways to prevent cutworm infestations:
- Before planting your tomato seedling, check the soil for cutworms. Since these worms love to hide in the soil, you may need to dig and turn the soil thoroughly to make sure that there are no cutworms lying in wait.
- Use a collar to protect seedlings. These can be easily made using a cardboard strip, aluminum foil, cans, paper cups, or simply paper, and placed around the stem to act as a blockade between the soil, where the worms reside, and the stem. Cutworms are incapable of climbing over these collars.
- Frequently tilling the soil will prevent cutworm colonies from setting up. Make sure you remove all the plant waste after tilling and before planting your tomatoes.
- Check your tomato plants at night using a torch. If you spot any cutworms on the plant, simply pick them off by hand and suffocate them in a jar of soapy water.
- Cornmeal is known to kill cutworms, so spreading cornmeal around the plant will kill the cutworms.
- Cutworms spend the winter in dead plant matter, so make sure all debris is cleared often. Tilling the soil in the spring will also expose any hidden cutworms.
- Frequently watering your plants may also interfere with the worms’ functioning.
- Planting varieties that attract cutworm predators, such as hedgehogs, birds, and beetles, can also be quite effective at preventing cutworm infestations.
5. Leafhoppers
Leafhoppers, if left untreated, can be quite a problem for your tomatoes. These pests suck the sap from the stems and leaves of the plant; this results in the leaves curling, spotting, and/or yellowing.
More dangerous, though, is the transmission of pathogens that these pests are responsible for. These pathogens can cause serious tomato diseases to the plant and also spread quickly to other plants.
Adult leafhoppers can be identified by their wedge-shaped, slender bodies. These pests are typically a quarter of an inch long. Leafhoppers come in a range of colors; some are extremely colorful while some are plainer and blend into the plant.
Their most distinctive feature is that these pests move sideways in crab-like movements.
Preventing/Treating Leafhopper Infestations
Some measures that work to prevent and treat leafhopper infestations:
- Strong jets of water, similar to what was described for aphids.
- Row covers, especially when dealing with large infestations.
- Plants that attract predatory insects and birds.
6. Potato Aphids
Potato aphids are common vegetable garden pests that can be found across North America.
These pests attack potato and tomato plants and can be identified by their wingless bodies, typically light green, pink and green, or solid pink, and the thin, long cornicles extending from their body. These are also the largest aphids in the family.
Potato aphids usually aren’t severe enough to kill a plant, but they can cause substantial damage by piercing the blooms, stems, and veins of the plant. The damage causes the blooms to fall off, reducing the yield from the plant and causing curling and stunting.
Extremely severe infestations can cause the plant to turn brown and eventually die.
Preventing/Treating Potato Aphid Infestations
Potato aphids can be prevented and treated in the same manner that is followed with all aphids. However, if the potato aphid is winged, predatory insects, such as parasitic wasps and lacewing, are the most effective.
7. Blister Beetles
Blister beetles aren’t just harmful to your tomato plants; they’re also harmful to humans.
These beetles release a little something known as cantharidin, a blistering agent (hence, the name), when injured or crushed. This agent is quite harmful to bare skin.
Blister beetles can be identified by their bright orange heads and black bodies.
Preventing/Treating Blister Beetle Infestations
Blister beetles can be prevented and treated in the following ways:
- Anchored row covers work well in areas suffering from large infestations.
- If the infestation isn’t severe, these pests can be picked off by hand. Make sure that you use gloves so that you aren’t harmed by the cantharidin released by the beetles. The picked-off beetles can be suffocated in soapy water.
- Attracting birds to your garden can help keep down blister beetle numbers, as birds love to feast on these.
8. Hornworms
Hornworms are the (harmful) caterpillars of the five-spotted hawkmoth. These pests can grow up to three inches in length, and with their light green coloring, are capable of easily camouflaging themselves among plants and foliage. This makes them hard to spot and exterminate.
However, tomato hornworms can be easily identified once spotted, thanks to the presence of a black, straight horn protruding from its tail end (the horn isn’t harmful).
Hornworms are non-stop feeders and can cause substantial damage by laying eggs on the leaves’ undersides, attacking the fruits, and eating the leaves of the plant.
Both tomato and tobacco hornworms can infest tomato plants. Both are common across the United States.
Preventing/Treating Hornworm Infestations
Hornworms can be fended off with the following measures:
- Since hornworms are quite large, they can be easily picked off by hand. Black or dark green droppings on the leaf surface can indicate the presence of these pests, which are usually found on the underside of leaves.
- Before planting your tomato sapling, check surrounding plants for signs of these pests. Additionally, regularly monitor your tomato plants once planted.
- Introducing predatory insects and companion plants will also help repel hornworm infestations.
9. Leaf Miners
Leaf miners are small flies that can be identified by the bright yellow dot on their backs. These pests are extremely harmful to tomato plants in both adult and larvae forms; while adults feed on the foliage, the larvae eat through the leaf’s inside.
Leaf miners lay eggs on the underside of the leaf. When these eggs hatch, the larvae eat through the leaf, interrupting the plant’s photosynthesis abilities. A severe enough infestation could quickly kill the plant.
Leaf miner larvae are thankfully easy to identify due to the white trails they leave on the leaves while they eat through them.
Preventing/Treating Leaf Miner Infestations
Some ways to prevent and treat leaf miner infestations:
- When you see the white trail described above on a leaf, immediately cut it off and check the plant for other signs of infestation.
- Again, introducing natural predators can prevent and overcome leaf-miner infestations.
- Keep your garden clean of any plant and weed debris, as these can attract leaf miners.
10. Tomato Root-Knot Nematodes
Also known as eelworms, tomato root-knot nematodes are tiny worms that live in the soil. These worms become parasites by laying eggs on the plant’s roots, sucking in all the nutrients that would otherwise go to the plant’s fruits, flowers, and leaves for their growth.
This causes the plant’s growth to become erratic and slow, which further results in smaller tomato plants and reduced yield.
Some signs of nematode infestation are yellowing leaves, wilting, and lumps/knobs on the roots. Nematodes can spread quite easily.
Preventing/Treating Tomato Root-Knot Nematodes
Some ways to prevent and treat root-knot nematodes include:
- Treating the soil with chitin-containing substances, such as seafood meal, may prevent the concentration of nematodes.
- Rotating the crop every year and regularly tilling the soil can also help prevent nematode infestations, as these pests need time to establish themselves in the soil.
- Since nematodes can spread easily by hiking a ride on a range of mediums, including your tools, boots, and gloves, make sure you sanitize all your equipment thoroughly. Contaminated equipment should be sterilized with a bleach solution.
- Remove any infected plants and soil as plants cannot recover from a nematode infestation. Discard the infected parts and soil that you’ve removed; do not throw them back on the ground or compost them as the infestation can spread.
- Marigolds are excellent companion plants to keep down nematode concentrations, especially in areas where infested soil cannot be removed. Once the marigolds flower, bury them in the soil. The decomposing marigolds can prevent nematodes as they release a chemical that the former detests.
- You could also opt for nematode-resistant tomato varieties (differentiated by an “N” under or next to the name of the plant).
11. Tomato Fruit Worms
Also known as cotton bollworms and corn earworms, tomato fruitworms are moth larvae that hatch from eggs laid on tomato plants. These long pests are typically gray or striped yellow, feeding on the leaves and fruits of the plant from the inside out.
Spotting tomato fruitworms can be tricky since it takes a while for the impact of the internal damage caused by these worms to manifest on the outside.
Preventing/Treating Tomato Fruitworm Infestations
Some ways to prevent tomato fruitworms include:
- Monitor your tomato plant for these pests. Initially white, fruitworm eggs turn brown just before the larvae are ready to hatch. Destroy any eggs and larvae that you see.
- If there are a lot of larvae, introducing natural predators, such as big-eyed bugs, pirate bugs, and Trichogramma will help keep down fruitworm infestations.
- Till the soil during the fall season to expose any eggs. Exposed eggs will be killed off by the cold.
- Insecticides such as garlic spray and other worm and caterpillar sprays can keep away tomato fruitworms.
12. Psyllids
The migratory pests that they are, psyllids are a threat during the winter as they tend to overwinter in areas with a warm climate. While this means that there’s lesser cause for worry (you don’t need to worry about recurring infestations), psyllids can still do considerable damage.
Psyllids are about the same size as an aphid and resemble cicadas. Spotting them may be challenging because of their small size, but these pests excrete psyllid sugar, which are wax-covered pellets, that collect on calm, undisturbed leaves and clue you in on the pests’ presence.
Additionally, yellowing leaves are among the first indicators of psyllid infestations.
Preventing/Treating Psyllid Infestations
Some ways to prevent and treat psyllid infestations:
- Use sticky paper to trap mature psyllids.
- Predatory insects and bugs, such as damsel bugs, pirate bugs, and spiders, can keep psyllid infestations at bay.
13. Thrips
Thrips can be quite damaging to tomato plants. These small flying insects are hard to detect, and before you know it, can feed on flower beds, new leaves and stems, and seedlings, causing young plants to droop and their growth to slow.
More pressingly, thrips are responsible for spreading tomato spotted wilt virus, an untreatable virus that is highly contagious and can affect your whole garden.
Preventing/Treating Thrips Infestations
Some ways to prevent thrips infestations include:
- Grow plants that attract natural thrips predators, such as mites, pirate bugs, and ladybugs. Some options include dill, coriander, and Queen Ann’s lace.
- Control weed growth as this can attract thrips.
14. Whiteflies
Similar to aphids, whiteflies are more common in greenhouses and in indoor tomato plants. These pests suck out the sap from the stem and leaves of the plant, causing its health to deteriorate and the yield to go down.
Preventing/Treating Whitefly Infestations
Some ways to prevent and treat whitefly infestations:
- Whitefly populations can be controlled with the same measures used to control aphids.
- Spraying water directly on the leaves’ undersides will help remove whiteflies.
- Large infestations can be kept at bay with horticultural oils that suffocate the pests.
- Predatory insects such as ladybugs will also help control the whitefly population.
15. Spider Mites
Spider mites occur in large groups, usually found on the underside of leaves. Spider mites enjoy dry, hot weather, and their presence can be detected by delicate webs woven around the stems and leaves of the plant.
Spider mites are hardy and resistant to many insecticides and sprays. However, they detest cold water.
Preventing/Treating Spider Mite Infestations
Some ways to prevent spider mite infestations:
- As mentioned earlier, spider mites hate cold water. Spraying the plant twice a day with cold water will get rid of spider mites.
- Aromatic companion plants, such as chamomile, chives, and garlic, can repel spider mites and keep your tomato plants safe.
Bottom Line
Tomato plants are excellent additions to any kitchen garden, whether you’re an experienced gardener or are looking for a great vegetable starter plant.
Pest attacks can be frustrating, but with the right measures, you can easily fend off these and keep your tomato plants healthy and productive.
Now that you’re equipped with all the techniques to keep these pesky pests away, we hope you’ll grow some gorgeous tomato plants in your garden. Happy gardening!
