Tomato Pests: What Is Eating or Damaging My Plants?
Tomatoes can attract insects, mites, slugs, snails and larger animals. Some pests remove entire sections of leaf, while others pierce the plant and leave little visible evidence beyond curling, yellowing or distorted growth.
Not every hole or marked fruit requires treatment. A mature tomato plant can tolerate a limited amount of leaf damage without losing its crop. The priority is to identify what caused the damage and decide whether it is increasing.
Pest species differ between regions, but the method of diagnosis remains the same: examine the damage, inspect the entire plant and look for the pest itself or the evidence it leaves behind.
Begin With the Type of Damage
Ask what part of the plant is affected.
Missing Leaf Tissue
Look for:
Holes
Ragged edges
Skeletonised leaves
Entire leaflets disappearing
Bare leaf stalks
Droppings beneath damaged foliage
Likely causes include caterpillars, beetles, slugs, snails, grasshoppers and locusts.
Curled or Distorted Growth
Check for:
Aphids
Whiteflies
Thrips
Mites
Other sap-feeding pests
These pests often gather on tender growing tips or the undersides of leaves.
Pale, Speckled or Bronzed Leaves
Fine stippling or bronzing may be caused by mites, thrips or other sap-feeding pests.
Tunnels Within Leaves
Pale, winding trails inside the leaf are usually caused by leaf miners.
Holes or Scars on Fruit
Possible causes include:
Caterpillars
Beetles
Slugs and snails
Stink bugs and related sap feeders
Birds
Rodents
Other wildlife
Wilting or Cut Stems
Inspect for:
Cutworms
Stem-boring larvae
Root-feeding pests
Physical damage
Tight plant ties
Root-knot nematodes
Inspect the Plant Carefully
Many tomato pests hide during the day or remain beneath the leaves.
Check:
Both sides of every affected leaf
The growing tip
Leaf joints
Flower trusses
Beneath the fruit calyx
Inside damaged tomatoes
The main stem
The base of the plant
The soil and mulch beneath it
Plant ties and supports
Look for:
Eggs
Larvae
Cast skins
Webbing
Sticky honeydew
Droppings
Feeding scars
Tiny puncture marks
The pests themselves
Inspect plants at different times. Slugs, snails and some caterpillars are more active after dark, while beetles may be easier to see once temperatures rise.
Aphids
Aphids are small, soft-bodied insects that gather on tender shoots, young leaves and flower stems.
They may be green, black, grey, yellow, pink or brown.
Signs of Aphids
Look for:
Clusters of small insects
Curled or distorted new growth
Sticky honeydew
Ants moving over the plant
Dark sooty mould growing on honeydew
White shed skins
Weak or stunted shoots in severe infestations
A small aphid colony may cause little harm to an established plant. Large populations can weaken growing tips and may transmit plant viruses.
Managing Aphids
Begin with the least disruptive methods:
Crush small colonies by hand
Remove a heavily infested growing tip only when necessary
Dislodge aphids with a controlled stream of water
Encourage ladybirds, lacewings, hoverflies and parasitic wasps
Control ants if they are protecting aphid colonies
Inspect plants regularly
Avoid removing large amounts of healthy growth.
If a treatment is needed, use a product approved for organic growing and legally authorised for tomatoes and aphids in your location.
Whiteflies
Adult whiteflies are small, pale insects that fly up when disturbed. Their immature stages remain on the undersides of leaves.
Signs of Whiteflies
Look for:
Small white insects flying from the plant
Flat immature stages beneath leaves
Yellowing foliage
Sticky honeydew
Sooty mould
General plant weakness during heavy infestations
Whiteflies can reproduce quickly in greenhouses and other protected spaces.
Managing Whiteflies
Inspect new plants before introducing them
Remove heavily infested leaves without over-pruning
Use suitable monitoring traps under cover
Improve access and airflow
Encourage or introduce appropriate biological controls
Remove weeds that support the pest
Avoid unnecessary broad-spectrum pesticides
Monitoring traps help reveal the presence of adult whiteflies but rarely control an established infestation by themselves.
Spider Mites
Spider mites are extremely small and can be difficult to see without magnification.
They thrive particularly in hot, dry conditions.
Signs of Spider Mites
Look for:
Fine pale dots across the leaves
Yellowing or bronzing
Dry, brittle foliage
Fine webbing between leaves and stems
Tiny moving mites beneath the leaves
Leaf drop during severe infestations
Mite damage can initially resemble drought stress or nutrient deficiency.
Managing Spider Mites
Act before extensive webbing develops.
Remove only the worst affected leaves
Avoid allowing plants to become severely drought-stressed
Wash mites from the undersides of leaves where practical
Maintain good plant health
Use suitable biological controls under cover
Avoid pesticides that unnecessarily kill predatory insects and mites
Monitor nearby plants
Do not increase greenhouse humidity without considering fungal disease and general ventilation.
Tomato Russet Mites
Tomato russet mites are even smaller than spider mites and are usually not visible without magnification.
Signs of Russet Mites
Possible symptoms include:
Bronzing beginning on lower stems and leaves
Dry, brown foliage
Leaves curling upwards
Stems taking on a rusty appearance
Damage progressing upwards
Small or russeted fruit
General decline during warm conditions
These symptoms can resemble disease, drought or chemical injury. Microscopic examination may be needed for confirmation.
Remove severely affected material and seek local advice on suitable controls where the pest is confirmed.
Thrips
Thrips are slender insects that feed on leaves, flowers and young fruit.
Signs of Thrips
Look for:
Silvery or bronze feeding scars
Distorted young leaves
Damaged flowers
Tiny dark specks of waste
Pale marks on fruit
Small, narrow insects moving within flowers
Some thrips can transmit tomato viruses, including tomato spotted wilt virus.
Managing Thrips
Inspect flowers and growing tips
Remove weeds that may act as hosts
Use monitoring traps under cover
Encourage natural predators
Remove badly affected material
Avoid bringing infested plants into a greenhouse
Use only treatments approved for organic growing and legally authorised for tomatoes and the identified pest in your location
Because thrips may hide inside flowers, a quick inspection of the leaf surface may miss them.
Leaf Miners
Leaf miners are larvae that feed between the upper and lower surfaces of a leaf.
Signs of Leaf Miners
Look for:
Pale winding trails
Blotched mines
A dark line of waste within the trail
A small larva or pupa inside the leaf
Damage limited to the internal leaf tissue
A small amount of leaf-miner damage is mostly cosmetic.
Managing Leaf Miners
Crush the larva within the visible tunnel
Remove heavily mined leaves where necessary
Do not strip large amounts of healthy foliage
Use protective mesh where the local leaf-miner species makes this practical
Remove affected crop debris
Encourage parasitic wasps
Contact sprays are often ineffective against larvae protected inside the leaf.
Flea Beetles
Flea beetles are small beetles that jump when disturbed.
They create numerous tiny holes, often described as shot holes, across the leaves.
Young tomato plants are more vulnerable than established plants because they have little foliage to spare.
Managing Flea Beetles
Protect young plants with suitable insect mesh
Keep seedlings growing steadily
Remove weeds that host the beetles
Encourage ground beetles and other predators
Use physical barriers before damage begins
Monitor newly planted tomatoes closely
Older plants can usually tolerate limited flea-beetle feeding.
Colorado Potato Beetles
Colorado potato beetles feed on tomatoes as well as potatoes, aubergines and other related plants.
Identifying Colorado Potato Beetles
Look for:
Yellow-orange eggs in clusters beneath leaves
Red-orange larvae with dark spots
Striped adult beetles
Leaves eaten from the edges
Rapid defoliation during heavy infestations
The larvae can consume large amounts of foliage as they grow.
Managing Colorado Potato Beetles
Inspect leaf undersides for egg clusters
Crush or remove eggs
Hand-pick larvae and adults
Check related crops nearby
Remove volunteer potatoes and other host plants
Rotate susceptible crops where practical
Encourage natural predators
Use a targeted treatment approved for organic growing and legally authorised for tomatoes in your location only when necessary
Regular inspection is more effective than waiting until large larvae have caused extensive defoliation.
Blister Beetles
Blister beetles can gather in groups and remove foliage rapidly. Species and behaviour vary by region.
They may feed on tomatoes, peppers, beetroot, weeds and other crops.
Signs of Blister Beetles
Look for:
Groups of elongated beetles
Ragged or stripped foliage
Plants being defoliated rapidly
Beetles dropping to the ground when disturbed
Damage spreading quickly through a row
Some blister beetles contain cantharidin, a chemical capable of blistering skin and harming animals if consumed.
Managing Blister Beetles
Wear gloves when handling them
Do not crush them against bare skin
Hand-pick or collect them into a suitable container
Shake or tap them from plants onto a sheet or tray
Inspect plants during cooler periods when beetles may be less active
Protect small plantings with suitable mesh
Encourage insect-eating birds where appropriate
Use controls approved for organic growing and legally authorised for tomatoes in your location only when necessary
Keep collected beetles away from livestock feed and areas where animals could consume them.
Caterpillars
Several caterpillars feed on tomato foliage and fruit. Their names and species vary between regions.
Common groups include:
Tomato and tobacco hornworms
Fruitworms
Armyworms
Loopers
Cutworms
Leaf-rolling caterpillars
Signs of Caterpillars
Look for:
Chewed leaves
Entire leaflets missing
Large dark droppings
Rolled or webbed leaves
Holes in green or ripening fruit
Larvae hidden beneath foliage
Damage concentrated near the growing tip
Caterpillars can be difficult to see because their colouring often matches the plant.
Hornworms
Hornworms are large green caterpillars with diagonal markings and a horn-like projection at the rear.
They can remove large amounts of foliage quickly.
Look for their dark droppings beneath damaged leaves. Follow the damage and droppings upwards to locate the caterpillar.
Fruitworms and Armyworms
These caterpillars may feed on leaves, flowers and fruit.
Damaged tomatoes may contain:
Round entry holes
Chewed cavities
Droppings
Larvae
Secondary decay
Remove damaged fruit and inspect neighbouring tomatoes.
Managing Caterpillars
Hand-pick visible larvae
Search near fresh droppings
Remove rolled leaves containing caterpillars
Encourage birds, predatory insects and parasitic wasps
Inspect plants frequently
Use suitable protective mesh against egg-laying adults
Apply a Bacillus thuringiensis product approved for organic growing and legally authorised for tomatoes in your location where appropriate
Bacillus thuringiensis products work on specific groups of young larvae that consume treated foliage. They do not control beetles, aphids, mites or mature caterpillars that are no longer feeding actively.
Leave a caterpillar carrying the visible white cocoons of parasitic wasps undisturbed where it is safe to do so. The wasps developing from those cocoons can help control other caterpillars.
Cutworms
Cutworms are caterpillars that hide in soil or mulch and feed near ground level, often at night.
Signs of Cutworms
Look for:
Young plants cut through near the soil
Damaged lower stems
Seedlings collapsing suddenly
Caterpillars curled in the soil near the plant
Night-time feeding
Managing Cutworms
Search the soil around damaged plants
Hand-pick caterpillars
Use collars around young stems
Keep heavy plant debris away from newly planted seedlings
Check plants after dark
Encourage ground beetles and birds
Established tomato stems are usually less vulnerable than tender young transplants.
Beetles and Other Leaf-Eating Insects
A range of regional beetles may chew tomato foliage.
Damage may appear as:
Small holes
Ragged edges
Skeletonised leaves
Missing growing tips
Rapid defoliation
Identify the beetle before choosing a response. A beetle found on a damaged plant may be a predator rather than the pest responsible.
Hand-picking and protective barriers are often sufficient for small plantings.
Grasshoppers and Locusts
Grasshoppers and locusts remove irregular sections from leaves and may also damage stems and fruit.
They can be particularly destructive during dry periods or regional population outbreaks.
Signs of Grasshopper or Locust Damage
Look for:
Ragged leaf edges
Large sections of missing foliage
Feeding on several types of plant
Strong-jumping insects
Damage progressing from surrounding vegetation
Scarred fruit
Managing Grasshoppers and Locusts
Options are limited once large mobile insects are established.
Helpful measures include:
Protecting important plants with suitable mesh
Hand-catching where numbers are low
Reducing unmanaged vegetation immediately beside vulnerable crops where appropriate
Encouraging birds and other predators
Acting while insects are still young
Following regional outbreak guidance
Do not enclose plants so tightly that airflow and pollinator access are unnecessarily restricted.
Slugs and Snails
Slugs and snails feed mainly at night or during damp weather.
Signs of Slug and Snail Damage
Look for:
Irregular holes
Ragged leaf edges
Surface grazing on fruit
Damage to low-hanging tomatoes
Silvery slime trails
Feeding concentrated near the ground
Managing Slugs and Snails
Inspect after dark
Hand-pick them
Remove hiding places near plants
Lift fruit away from the soil
Water in the morning rather than creating damp night-time surfaces
Use physical barriers where practical
Encourage natural predators
Use a bait approved for organic growing and legally authorised for use around tomatoes in your location where necessary
A badly damaged tomato should be removed because feeding wounds can allow decay to enter.
Stink Bugs and Shield Bugs
Stink bugs and related shield bugs pierce tomatoes and feed on their juices.
Signs of Stink-Bug Feeding
Look for:
Small puncture marks
Pale or yellow spots
Cloudy patches beneath the skin
Hard white tissue inside fruit
Uneven ripening
Distorted young tomatoes
Shield-shaped insects or egg clusters
The damage may become clearer as the fruit ripens.
Managing Stink Bugs
Hand-pick adults and young stages
Remove egg clusters
Keep weeds from becoming unmanaged host reservoirs
Use protective mesh where practical
Encourage predators and parasitoids
Inspect fruit and foliage regularly
These insects are mobile, so repeated monitoring may be necessary.
Leaf-Footed Bugs
Leaf-footed bugs are sap-feeding insects, some of which have flattened, leaf-like expansions on their hind legs.
Their feeding can cause:
Puncture marks
Pale areas
Internal hard tissue
Fruit distortion
Uneven ripening
Early fruit drop
Eggs may be laid in a line along leaves or stems.
Hand-picking, egg removal and protective barriers can help in small plantings.
Root-Knot Nematodes
Root-knot nematodes are microscopic worms that feed within plant roots.
Signs of Root-Knot Nematodes
Possible symptoms include:
Stunted plants
Yellowing
Wilting during warm weather
Poor response to watering or feeding
Reduced fruit production
Swollen knots or galls on the roots
Above-ground symptoms resemble several other root problems. Confirmation requires examination of the roots and may require laboratory diagnosis.
Managing Root-Knot Nematodes
Management may include:
Growing resistant varieties
Rotating with unsuitable host crops
Removing affected roots
Improving soil health
Preventing movement of contaminated soil
Using locally appropriate cover crops
Solarising soil where the climate and growing system make this effective
Rotation choices must reflect the particular nematode because many species have a wide host range.
Ants on Tomato Plants
Ants do not usually feed directly on tomato plants, but they may protect aphids, whiteflies or other honeydew-producing insects.
If ants are moving repeatedly up and down a tomato stem, inspect the leaves above them for sap-feeding pests.
Managing the honeydew-producing pest usually removes the ants’ reason for visiting the plant.
Birds
Birds may peck ripe tomatoes for moisture or food.
Signs of Bird Damage
Look for:
Clean peck holes
Wedge-shaped missing pieces
Damage concentrated on ripe fruit
Fruit damaged high on the plant
No slime trails or insect droppings
Protecting Tomatoes From Birds
Harvest ripe fruit promptly
Use wildlife-safe netting correctly
Provide a suitable water source during dry conditions
Use temporary visual deterrents
Keep fruit within a supported canopy
Netting must be secured and kept taut enough that birds and other animals cannot become trapped.
Rodents and Other Mammals
Mice, rats, squirrels and other mammals may remove or chew tomatoes.
Signs may include:
Large bites
Fruit disappearing
Droppings
Tracks
Damage occurring overnight
Tomatoes carried away from the plant
Use secure physical exclusion and remove fallen or damaged fruit promptly. Avoid leaving harvested or discarded produce near the growing area.
Pest Damage or Disease?
Pest damage is more likely when there are:
Holes
Missing tissue
Puncture marks
Droppings
Webbing
Sticky honeydew
Visible insects or eggs
Feeding trails
Disease is more likely when there are:
Expanding spots
Water-soaked lesions
Dark stem marks
Mould
Rapid tissue death
Wilting despite suitable moisture
Symptoms progressing through the plant
Some pests transmit diseases, and feeding wounds can become infected. A plant may therefore show both pest and disease symptoms.
When to Take Action
Treatment may be justified when:
Damage is increasing rapidly
The growing tip is threatened
Young plants are being defoliated
Flowers or fruit are being destroyed
A pest can transmit serious disease
Pest numbers are continuing to rise
Natural predators are not controlling the population
Observation may be sufficient when:
Damage is old and no longer increasing
Only a few leaves are affected
The plant remains vigorous
Predators or parasitised pests are present
The pest is no longer visible
The crop is not at risk
The presence of an insect does not automatically mean that it must be killed. Many insects found on tomatoes are predators, pollinators or harmless visitors.
Hand-Picking Tomato Pests
Hand-picking is one of the most targeted control methods for visible pests.
Use gloves where appropriate, particularly when handling:
Blister beetles
Hairy or spiny caterpillars
Unknown insects
Pests that release irritating substances
Place collected pests into a secure container. Do not simply move them to another part of the growing area.
Protective Mesh and Covers
Physical barriers can prevent adult insects from laying eggs or reaching young plants.
They work best when:
Installed before pests arrive
Secured at the edges
Kept away from the foliage
Checked for trapped insects
Removed or opened when pollinator access is required
Used without restricting airflow excessively
Tomatoes are self-fertile, but flower movement and insect activity can improve pollination. Covered plants may need gentle manual vibration during flowering.
Encouraging Natural Predators
Tomato pests are eaten or parasitised by:
Ladybirds
Lacewing larvae
Hoverfly larvae
Predatory bugs
Parasitic wasps
Ground beetles
Spiders
Birds
Predatory mites
Provide flowering plants, varied habitats and water sources while avoiding unnecessary broad-spectrum pesticides.
Natural control takes time. Regular observation helps determine whether predators are reducing the infestation.
Using Sprays Responsibly
Do not spray until the pest has been identified.
A treatment for aphids may not control mites, caterpillars or beetles. Some products can also harm pollinators and natural predators.
Before applying anything:
Confirm the pest is still present.
Check whether damage is increasing.
Use the least disruptive effective method.
Ensure the product is approved for organic growing and legally authorised for tomatoes and the identified pest in your location.
Follow the label exactly.
Observe the harvest interval.
Avoid spraying open flowers when pollinators are active.
Avoid applying sprays during extreme heat or intense sunlight.
Test any contact treatment on a small area first where appropriate.
Homemade mixtures can also burn foliage or fruit. “Natural” does not mean harmless to plants, insects or the gardener.
Removing Pest-Damaged Leaves
Remove a leaf when it is:
Heavily infested
Containing pest eggs or larvae that cannot otherwise be removed
Mostly destroyed
No longer functioning
Beginning to decay
Do not remove every leaf with a hole or feeding mark.
Excessive leaf removal can:
Reduce photosynthesis
Slow fruit development
Expose tomatoes to sunscald
Increase heat stress
Reduce the eventual crop
Established tomatoes can tolerate a limited amount of leaf damage.
Removing Pest-Damaged Fruit
Remove fruit that is:
Extensively chewed
Containing larvae
Soft or leaking
Mouldy
Contaminated
Beginning to decay
A fruit with a minor superficial feeding scar may remain usable if the skin and flesh are otherwise sound. Harvest it promptly and inspect it carefully.
A Quick Tomato-Pest Checklist
New growth is curled and sticky
Check for aphids or whiteflies.
Leaves are finely speckled with webbing
Check for spider mites.
Stems and lower foliage appear bronze or rusty
Investigate tomato russet mites.
Leaves have silvery scars and tiny dark specks
Check for thrips.
Winding trails appear inside leaves
Look for leaf miners.
Many tiny holes appear in young leaves
Check for flea beetles.
Leaves disappear rapidly and striped beetles or orange larvae are present
Check for Colorado potato beetles.
Groups of elongated beetles strip foliage
Consider blister beetles.
Large sections of foliage disappear with dark droppings nearby
Search for caterpillars.
A young stem is cut near soil level
Look for cutworms.
Irregular holes and slime trails appear near the ground
Check for slugs and snails.
Fruit develops pale puncture marks and hard internal areas
Check for stink bugs or leaf-footed bugs.
Entire plants are stunted and roots have swollen knots
Investigate root-knot nematodes.
Ripe fruit has clean peck holes
Birds are the likely cause.
Monitor Before the Damage Becomes Severe
The most effective pest management begins with regular inspection.
Check tomato plants often enough to notice:
The first egg clusters
Small caterpillars
Early aphid colonies
Fine mite damage
New leaf mines
Fresh fruit wounds
Small, localised infestations are easier to manage than pests that have spread through dense foliage.
Identify the cause, protect beneficial wildlife and match the response to the seriousness of the damage. Most tomato plants can tolerate some feeding and still produce a good harvest. Intervention is most useful when it is timely, targeted and no greater than the problem requires.
For complete advice on growing healthy tomato plants from sowing through to harvest, return to How to Grow Tomatoes: Complete Guide.
