Holes in pepper fruits are almost always the work of an insect pest, though slugs, snails, and occasionally birds or rodents can be responsible too. The shape, size, and location of the damage usually points straight to the culprit. A small, perfectly round exit hole signals a pepper weevil. Tiny elliptical punctures on young fruit suggest the pepper maggot. Irregular, ragged chewing with slime residue means slugs or snails. And large, messy cavities eaten from the outside are the signature of caterpillars or cutworms. Figuring out which creature is responsible matters, because the control strategies differ sharply from one pest to the next.
Pepper Weevils and Their Telltale Round Holes
The pepper weevil is one of the most destructive fruit-boring pests of peppers worldwide, and its damage is distinctive. Adult females chew a small cavity into the pepper’s skin and deposit eggs inside, then seal the opening with a secretion that hardens into a plug ranging from translucent to dark brown. That plug actually contains chemicals that deter other females from laying in the same fruit, so each puncture tends to represent a single egg event. Larvae hatch after about four days, then feed inside the fruit for roughly twelve days before pupating. When the new adult is ready to emerge, it chews a clean, circular exit hole through the fruit wall.1Journal of Integrated Pest Management. An Overview of the Pepper Weevil as a Pest of Greenhouse Peppers
If you crack open an infested pepper, you’ll often find brown frass, partially hollowed seeds, and sometimes the larvae or pupae themselves still inside. Infested fruit frequently drops from the plant prematurely. The real frustration with pepper weevils is that the larvae spend their entire development hidden inside the fruit, which severely limits the effectiveness of contact insecticides sprayed on the outside.2Plant Health Cases. Efficacy of Plinazolin and Selected Conventional Insecticides for Control of Pepper Weevil (Anthonomus eugenii) Adults: A Laboratory Bioassay By the time you see the exit hole, the weevil has already completed its lifecycle and left. This means control efforts have to target the adult stage, before the female lays her eggs.
Pepper Maggots Leave Smaller, Elliptical Marks
Pepper maggots are the larvae of a fruit fly that targets peppers specifically. The damage pattern is different from the weevil’s: instead of a round exit hole, the first visible sign is a tiny elliptical puncture on the surface of young, still-growing fruit. These holes are extremely small, roughly half a millimeter long, and they appear on peppers that are still well under two inches in diameter. The holes are made by the female fly’s egg-laying organ as she inserts eggs just beneath the skin. After hatching in eight to ten days, the maggots burrow deeper into the fruit and feed for two to three weeks.3Virginia Cooperative Extension. Pepper Maggot, Zonosemata electa, in Sweet (Bell) Pepper
The internal damage from pepper maggots is often worse than it looks from outside. Infested fruit may appear almost normal until you cut it open and find tunnels, decay, and mushy tissue. Because the maggot feeds quietly inside the fruit wall, you can harvest a pepper that looks fine and only discover the problem in the kitchen. Unlike pepper weevils, which tend to cause premature fruit drop, maggot-infested peppers sometimes stay on the plant and ripen, masking the infestation until harvest.
Caterpillars and Cutworms
If the holes in your peppers are large, jagged, and clearly chewed from the outside, a caterpillar is the most likely suspect. Several moth species lay eggs on pepper plants, and their larvae feed on both foliage and fruit. Corn earworms, tobacco budworms, and various armyworm species are common offenders in home gardens. They tend to bore into the fruit from the stem end or the side, creating irregular cavities packed with dark, pellet-shaped droppings. Unlike weevils and maggots, caterpillars are often visible if you look carefully at night or early morning, since many species feed after dark.
Cutworms deserve a special mention. These thick, curling caterpillars live in the soil during the day and climb plants at night to feed. A study on the common cutworm attacking bell peppers found that unprotected plants suffered devastating fruit losses, with most harvested fruit rendered unmarketable by chewing damage.4Journal of Agricultural Sciences – Sri Lanka. Netting and Bagging: An Eco-Friendly Management Approach against the Common Cutworm (Spodoptera litura Fab.) of Bell Pepper If you find large, smooth-bodied caterpillars curled up in the soil at the base of your pepper plants during the day, cutworms are your problem.
Slugs, Snails, and Their Telltale Slime
Not every hole-maker has six legs. Slugs and snails chew irregular, shallow gouges in pepper fruit, often on the side resting closest to the ground or touching a leaf. The giveaway is a shiny slime trail on or near the damaged fruit. Slug and snail damage tends to be worst in rainy weather, particularly during prolonged wet periods with warm temperatures and high humidity.5Academia.edu / Plant Archives. SEASONAL INCIDENCE, VARIETAL PREFERENCE AND MANAGEMENT OF GARDEN SNAIL, HELIX ASPERSA IN CAPSICUM In one study on capsicum varieties, snail damage resulted in economic losses around 12.5% of the crop, with thin-walled, lighter-colored varieties suffering the worst infestation.
Slug and snail control is mostly about habitat management. These creatures need moisture and hiding places during the day: mulch, debris, low-hanging foliage, and boards left on the ground all provide shelter. Reducing ground-level moisture around your pepper plants, hand-picking at night with a flashlight, and using iron phosphate baits are the standard approaches. Copper tape around raised beds can also deter them, since contact with copper produces an unpleasant reaction in their mucus.
How to Identify the Culprit
When you find a damaged pepper, resist the urge to toss it immediately. The damage pattern itself is your best diagnostic tool. Here’s what to look for:
- Round exit hole: A clean, circular hole roughly the diameter of a pencil lead, usually on fruit that has dropped from the plant, points to the pepper weevil. Cut the fruit open and look for pupal cases or frass inside.
- Tiny elliptical punctures: Very small, elongated holes on young, small fruit suggest pepper maggot oviposition. The holes are barely visible without close inspection.
- Large, irregular cavities: Ragged, chewed-out sections with dark droppings inside indicate caterpillars. Check the stem end of the fruit and the underside of nearby leaves for larvae or eggs.
- Shallow surface gouges with slime: Irregular, scooped-out areas on the side of the fruit nearest the ground, accompanied by silvery trails, mean slugs or snails.
- Clean bites with teeth marks: If large chunks are missing and you see no insect evidence, consider birds, squirrels, or rats. Mammal teeth leave distinct paired grooves.
The timing of the damage also helps. Pepper weevils and maggots cause damage throughout the fruiting season but tend to be worse as the season progresses and populations build. Cutworm damage is often most severe on young transplants and early-set fruit. Slug damage spikes after rain.
Why Hot Peppers Get Chewed Less
Gardeners who grow both sweet bell peppers and hot varieties often notice that the hot peppers suffer less insect damage. This isn’t coincidence. Capsaicin, the compound responsible for the burning sensation in hot peppers, acts as a chemical defense against many insect herbivores. In one study comparing caterpillar performance on peppers with different heat levels, larvae grew significantly larger and faster on non-pungent varieties. On the non-pungent pepper, caterpillars reached the pupal stage in 27 days. On a mildly hot variety, the same developmental stage took 33 days. On a highly pungent variety, it took 45 days, and none of the caterpillars that fed on those fruits survived to become adults.6PubMed Central. Altered capsaicin levels in domesticated chili pepper varieties affect the interaction between a generalist herbivore and its ectoparasitoid
That said, capsaicin isn’t a universal shield. Some moth species have evolved tolerance to it. The oriental tobacco budworm, a specialist on plants in the nightshade family, shows no significant reduction in growth when fed capsaicin-laced diets. Its mortality actually decreased on capsaicin compared to a plain diet, suggesting this species has adapted to use capsaicin-containing plants as a niche that competitors avoid.7PubMed. A host-plant specialist, Helicoverpa assulta, is more tolerant to capsaicin from Capsicum annuum than other noctuid species So while growing hotter pepper varieties can reduce generalist caterpillar damage, it won’t stop every insect. And of course, it doesn’t help if you’re specifically trying to grow sweet bell peppers.
Physical Barriers That Actually Work
For gardeners who prefer not to spray anything, physical exclusion is one of the most effective strategies. Fruit bagging, where individual fruits are enclosed in a paper or mesh bag while still small, physically prevents insects from reaching the fruit to lay eggs or feed. Research on bell peppers found that combining nylon netting over the plant canopy with individual fruit bagging reduced cutworm fruit infestation to about 11% and increased yield more than tenfold compared to unprotected plants.4Journal of Agricultural Sciences – Sri Lanka. Netting and Bagging: An Eco-Friendly Management Approach against the Common Cutworm (Spodoptera litura Fab.) of Bell Pepper White paper bags outperformed brown ones in fruit quality, likely because they transmitted more light and trapped less heat.
A parallel study on fruit bagging in apple orchards confirmed the broader principle: bagging provided pest protection equivalent to a conventional pesticide spray program for most direct fruit pests.8PubMed Central. Evaluation of Fruit Bagging as a Pest Management Option for Direct Pests of Apple The approach is labor-intensive, which makes it impractical for large commercial operations but well-suited to home gardens where you might be protecting a few dozen plants. For internal feeders like pepper weevils and maggots, bagging is especially valuable because it blocks the adult female from ever reaching the fruit to deposit eggs, eliminating the problem at its source.
Row cover fabric draped over the entire planting and secured at the edges offers broader protection with less per-fruit labor. The tradeoff is that you need to remove the cover or open it periodically for pollination, since peppers are insect-pollinated. Some gardeners solve this by lifting the row cover for a few hours each morning when bees are active, then replacing it.
Biological Control in Pepper Production
Commercial greenhouse pepper growers have increasingly turned to predatory insects and parasitic wasps as alternatives to chemical sprays. One well-studied system targets whiteflies, which don’t eat holes in fruit but weaken plants and spread viruses that reduce fruit quality. Research found that releasing the predatory mite Amblyseius swirskii alongside the parasitoid wasp Eretmocerus mundus significantly reduced whitefly populations beyond what either agent achieved alone.9Entomologia Experimentalis et Applicata. Development of a biological control‐based Integrated Pest Management method for Bemisia tabaci for protected sweet pepper crops The most effective approach combined these biological agents with a targeted pesticide application before the beneficial insects were released, knocking the initial pest population down so the biocontrol agents could keep it suppressed.
For backyard gardeners, the practical takeaway is simpler: avoid broad-spectrum insecticides that kill everything, because you want to preserve the natural enemies already present in your garden. Ground beetles eat slug eggs. Parasitic wasps attack caterpillar larvae and pepper weevil grubs. Lacewing larvae consume aphids that would otherwise weaken your plants. A garden that hasn’t been carpet-bombed with insecticide typically has enough beneficial predators to keep minor pest populations from exploding. When pest pressure is high enough to require intervention, targeted products like Bt (a bacterium that kills caterpillars but nothing else) or spinosad are far less disruptive to the broader ecosystem than broad-spectrum options.
How Weather Shapes Pest Pressure
The severity of insect and disease damage on peppers is strongly influenced by weather patterns. Research modeling pest and disease damage on pepper crops found that rising temperatures relative to historical averages significantly increased damage rates from several major pests and diseases. Higher humidity amplified the effect further.10Humanities and Social Sciences Communications. Analysis of social welfare impact of crop pest and disease damages due to climate change: a case study of dried red peppers This tracks with what most experienced gardeners already observe: hot, humid summers produce more caterpillars, more fruit flies, and more fungal infections that enter through insect-damaged openings.
In practical terms, this means your pest management needs shift year to year. A cool, dry summer might let you get away with minimal intervention, while a warm, wet one could require more aggressive scouting and control. Checking your plants at least twice a week during fruiting season is the single most useful habit. Catching an infestation early, when a few adult weevils or a single cluster of caterpillar eggs appears, is far easier than dealing with a full-blown population that’s already inside the fruit.
When Holes Lead to Rot
Any break in a pepper’s skin, whether made by an insect, a slug, or even hail, becomes an entry point for bacteria and fungi. You’ll sometimes find a pepper with a small, seemingly minor hole on the outside but a soft, foul-smelling cavity inside. That secondary rot is caused by opportunistic microorganisms that moved in through the wound. The initial pest damage may have been modest, but the resulting infection destroyed the fruit.
This is one reason prompt harvest matters when you’re dealing with an active pest problem. A pepper with a fresh weevil exit hole picked and brought inside the same day may still be perfectly edible once you cut away the damaged section. Left on the plant for another week, that same hole becomes a doorway for decay organisms, and the entire fruit turns to mush. During heavy pest pressure, harvesting peppers as soon as they reach usable size, even if they haven’t fully ripened, can salvage a much larger portion of your crop than waiting for perfect color.
Trap Crops and Garden Layout
Trap cropping is a strategy where you plant something that the pest prefers even more than your main crop, drawing the insects away from the peppers you actually want to eat. The concept is well established in pest management research, though results vary depending on the specific pest and how the trap crop is deployed. For caterpillar pests, planting a row of a highly attractive host plant (like certain flowering tobaccos or even sacrificial hot pepper plants of a variety you don’t mind losing) along the garden edge can concentrate egg-laying away from your prized bell peppers.
Garden layout decisions beyond trap cropping also matter. Pepper weevils overwinter in plant debris, so cleaning up all pepper plant residue at the end of the season and rotating where you plant peppers from year to year breaks the cycle. Avoid planting peppers near nightshade-family weeds, which can harbor both weevils and pepper maggot flies between growing seasons. Even spacing plants far enough apart for good air circulation reduces the moist, sheltered microclimate that slugs and snails prefer.
Staking or caging pepper plants so fruit hangs free of the soil also reduces slug access and makes it easier to spot damage during your regular garden walks. Small adjustments to how you arrange and maintain the garden often add up to a bigger reduction in damage than any single spray or treatment.