Pests
Symptoms Tiny soft green or black insects gather on new growth and the undersides of leaves, making them curl and yellow, often with a sticky film and black mold. Worse, aphids spread the viruses that stunt and mottle pepper plants.Colonies of small soft-bodied insects, often green peach aphid, cluster on growing tips and leaf undersides, curling and yellowing the leaves, with sticky honeydew and sooty mold following. On peppers the greater damage is indirect: aphids are the main vectors of the mosaic viruses that mottle and distort pepper foliage and stunt the plant, so aphid control is largely virus prevention. Cause Small sap-sucking insects that multiply quickly in warm weather, especially on soft growth from too much nitrogen. As they move around they spread plant viruses.Several aphid species, predominantly green peach aphid (Myzus persicae), that suck sap and reproduce rapidly in warm weather, building up fast on soft, over-fertilized growth. As they probe plant to plant they transmit cucumber mosaic and other viruses, which is why they head the pepper pest list. Organic treatment Blast them off with a strong spray of water and treat the undersides of the leaves with insecticidal soap, repeating every few days. Ladybugs and other helpful insects eat aphids, so welcome them.Knock colonies off with a strong jet of water and spray insecticidal soap or horticultural oil with thorough coverage of leaf undersides, repeating every few days. Conserve ladybugs, lacewings, and parasitic wasps, which usually bring aphids under control; reflective mulch deters them from young plants. Prevention Do not over-fertilize with nitrogen, check the undersides of leaves regularly, use reflective mulch on young plants, and let helpful insects do their work. Pull out any badly virus-stunted plants so aphids do not carry the disease onward.Avoid excess nitrogen, which drives the soft growth aphids favor, scout leaf undersides and growing tips, use reflective mulch on young plants, and support natural enemies rather than spraying broadly. Remove virus-infected plants promptly, since aphids spread the disease from them.
Symptoms The leaves are peppered with lots of tiny round holes, as if hit by birdshot. It hits young plants hardest. Touch the plant and you will see tiny dark beetles jump away.Tiny shot-hole punctures riddle the leaves, a scatter of small round holes that is the classic flea-beetle signature. Damage is most severe on seedlings and young transplants, whose small leaf area a heavy infestation can shred; established plants tolerate considerable feeding. Brush a plant and the small dark beetles spring away like fleas. Cause Small dark beetles that jump like fleas and chew tiny holes in the leaves. They are most active in spring and target young plants early in the season.Several flea beetle species (potato, tobacco, and palestriped among them) that feed on pepper foliage, overwintering as adults in debris and emerging to attack the earliest, most vulnerable plants in spring. NC State rates them minor pests of pepper, but they can set back small transplants badly. Organic treatment Cover young plants with a light row cover until they are big and strong, then take it off when they flower. Setting out larger transplants helps them outgrow the damage. For heavy attacks on seedlings, an organic spray such as spinosad or a kaolin clay coating helps.Protect transplants with floating row cover until they are large and vigorous, removing it at flowering so pollinators can reach the blooms. Set out stout, well-hardened transplants so plants can outgrow the damage, and treat heavy early infestations with spinosad or kaolin clay. Mature plants rarely need treatment. Prevention Cover plants early with row cover, set out larger transplants into warm soil so they grow quickly, and clear away weeds and old plant debris where the beetles hide over winter. A border of nasturtiums can lure them away.Use row cover from transplanting, delay setting plants out until the soil and air are warm so they grow away fast, and clean up crop debris and weeds that harbor overwintering adults. A nasturtium trap planting at the bed edge can draw beetles off the crop.
Symptoms Small pinprick scars appear on the pepper skin, and inside a maggot tunnels into the seed core, so the pepper ripens early and rots. It is mostly a problem in the Northeast. Good news for jalapeno: thin-walled hot peppers like it are rarely bothered, unlike thick bell peppers.A tiny white oviposition scar dimples the fruit surface where the fly laid an egg, and the maggot tunnels into the seed core inside; infested peppers often color up (turn red) prematurely and begin to rot from within. It is mainly a Northeastern and Mid-Atlantic pest, worst near tree lines. A useful jalapeno note: damage is negligible on slender, thin-walled peppers such as jalapeno and other hot types, which the maggot largely bypasses in favor of thick-walled bells. Cause The larva of a small fly that lays eggs inside pepper fruit in midsummer, mostly in the Northeast. The maggot eats the seed core. It prefers thick bell peppers, so jalapeno is rarely a target.The pepper maggot (Zonosemata electa), the larva of a striped fly that lays eggs in developing pepper fruit in July. Larvae feed inside the pod, then drop to the soil to pupate. Its host preference runs to thick-walled peppers, so hot, thin-walled types like jalapeno suffer little. Organic treatment There is no easy fix once the maggot is inside the fruit, so the main tools are covering plants with insect netting in mid-July when the flies lay eggs and picking off any scarred, prematurely reddening fruit. Jalapeno is rarely affected, so most growers need no action.Because eggs and larvae are protected inside the fruit, control targets the adult fly, and insecticides are the only reliable option where the pest is established. In a home garden, covering plants with insect netting during the mid-July egg-laying window and removing infested fruit are the practical non-chemical tools. Prevention Move peppers away from where they grew last year, clear weeds in the nightshade family nearby, and if pepper maggot is common where you live, cover plants with insect netting in mid-July. Growing jalapeno rather than thick bell peppers largely sidesteps this pest.Rotate peppers well away from last year's crop, control solanaceous weeds such as horsenettle that host the fly, cover the crop with insect netting during the mid-July egg-laying period, and disc or clear pepper residue promptly after harvest to kill larvae and pupae. Growing hot, thin-walled types like jalapeno is itself a strong cultural defense.
Symptoms Flower buds and small peppers turn yellow and fall off, and any pods that hang on are black and full of grubs and debris inside. The culprit is a tiny dark beetle. It is mainly a problem in the warm South and Southwest.Small buds and young fruit yellow and drop, and cut pods reveal a grub feeding at the seed core, the inside turned black and filled with frass. The adult is a small dark, brassy-lustered weevil about an eighth of an inch long. It is a serious pepper pest of the South and Southwest (including Florida, Texas, and southern California) and cannot overwinter where winters are cold. Cause A tiny beetle whose grubs grow up inside pepper buds and fruit, causing them to drop or rot from the inside. It lives year-round in warm areas and comes in from weeds and old pepper plants.The pepper weevil (Anthonomus eugenii), whose larvae develop inside buds and pods. Females lay eggs in flower buds and young fruit; the grubs feed at the seed core, causing bud and fruit drop and internal contamination. It breeds continuously in warm regions and reinvades from nightshade weeds and volunteer peppers. Organic treatment The main defense is cleanup: pick up and throw away every dropped or damaged pepper, since the grubs finish growing inside them, and check new plants before buying. Pull and destroy the plants as soon as harvest ends.Field sanitation is the core tool: remove and destroy dropped and culled fruit through the season, since larvae mature inside them, and inspect transplants so you do not bring the weevil in. Pheromone-baited sticky traps detect it early. In a home garden, destroying spent plants right after harvest sharply reduces the next year's population. Prevention Do not plant peppers where they grew last year, clear out nightshade weeds and any leftover pepper plants nearby, buy healthy transplants, and clean up the garden as soon as the season ends.Rotate away from last year's peppers, remove nearby nightshade weeds and volunteer pepper and eggplant that harbor the weevil, monitor with pheromone traps, source clean transplants, and destroy the crop promptly at season's end to break the continuous breeding cycle.
Symptoms Leaves vanish overnight, leaving bare stems, with dark droppings on the leaves below. The cause is a large green caterpillar that hides against the stems, easier to spot by its droppings than by sight.Large sections of leaf, and sometimes whole shoots or the odd fruit, are stripped overnight, with dark pellet droppings on the leaves below. The culprit is the big green tobacco (or tomato) hornworm, up to three and a half inches long, which blends into the stems and is easiest to find by its frass. Cause Big green caterpillars, the young of large moths, that feed on pepper and tomato leaves mostly in mid to late summer. Even a few can strip a lot of foliage.Tobacco and tomato hornworms, the larvae of large sphinx moths, which feed on solanaceous foliage including pepper from midsummer on. A few caterpillars can do conspicuous damage given their size, though peppers are a secondary host to tomato. Organic treatment Pick the caterpillars off by hand and drop them in soapy water. If you find one covered in small white capsules, leave it, those are parasitic wasps that will do the work for you. An organic Bt spray works on the smaller caterpillars.Hand-pick the caterpillars, which is effective in a home garden, and apply Bacillus thuringiensis to younger larvae where numbers are high. Leave any hornworm studded with white parasitic-wasp cocoons in place, since the wasps will kill it and breed more. Prevention Turn the soil at the end of the season to destroy the pupae, watch for droppings and missing leaves from midsummer, and welcome the helpful wasps that attack hornworms.Till the soil in fall to destroy overwintering pupae, scout for frass and stripped leaves from midsummer, and encourage the parasitic wasps and other natural enemies that keep hornworms in check.
Diseases
Symptoms The leaves get small dark, water-soaked spots that grow into brown patches with yellow edges, and badly spotted leaves yellow and fall, leaving fruit exposed. Rough, scabby spots also appear on the peppers. It is the most common serious pepper disease and spreads in warm, wet weather.Small, water-soaked spots on the leaves enlarge into brown, angular, sometimes scabby lesions with yellow halos, and heavy infection yellows and drops the foliage, exposing fruit to sunscald. Raised, scabby, cracked spots also form on the fruit, ruining it for use. It is the most common and damaging bacterial disease of peppers, worst in warm, wet, splashy weather. Cause A bacterium carried on seed and old plant debris that spreads in splashing water and on hands and tools when plants are wet. It thrives in warm, wet weather.Xanthomonas bacteria, carried on seed and in crop debris and spread by splashing water and handling wet plants. Warm, humid, rainy conditions favor it, and once established in a planting it is very hard to stop, so control is built on clean seed, resistant varieties, and keeping foliage dry. Organic treatment You cannot cure a plant that has it, so remove badly spotted plants and keep your hands and tools off wet foliage. Copper sprays can slow it a little, but prevention is what counts.There is no cure for an infected plant; remove badly affected plants to slow spread, avoid working among wet plants, and where pressure is high, copper-based sprays can suppress it, though resistance to copper is common. Management is preventive. Prevention Use clean seed and healthy transplants, look for resistant varieties, do not plant peppers in the same spot each year, water the soil rather than the leaves, and clean up old plants at the end of the season.Start with certified, pathogen-free or hot-water-treated seed and disease-free transplants, choose resistant varieties, rotate peppers on a 2 to 3 year cycle out of solanaceous beds, water at the soil to keep foliage dry, mulch to limit splash, space for airflow, and remove crop debris at season's end.
Symptoms The leaves turn a patchy light-and-dark-green mosaic and may pucker or narrow, and the plant is stunted with fewer, smaller peppers. Several viruses cause this, mostly carried by aphids.Leaves show a mottled light-and-dark-green mosaic, often puckered, narrowed, or distorted, and the plant stunts and sets fewer, smaller, sometimes misshapen or ringspotted fruit. Several viruses (cucumber mosaic, tobacco mosaic, and pepper-specific mottle viruses) cause the syndrome, most of them spread by aphids moving from plant to plant. Cause Viruses spread mainly by aphids, and some by hands, tools, and even tobacco products. Once a plant is infected there is no cure.A group of plant viruses, chiefly cucumber mosaic virus and tobacco mosaic virus, transmitted by aphids and, for the tobamoviruses, mechanically on hands and tools and through infected seed and tobacco products. There is no cure once a plant is infected, so control is aimed at the aphid vectors and at clean seed and sanitation. Organic treatment You cannot cure an infected plant, so pull and destroy it so aphids do not carry the virus to healthy plants. Control aphids, wash your hands, and do not touch peppers right after handling tobacco.There is no treatment for an infected plant; remove and destroy it promptly to cut the source of further spread, and control the aphids that move the virus. Wash hands and disinfect tools between plants, and do not handle peppers after using tobacco. Prevention Look for virus-resistant varieties, control aphids, keep weeds down, wash your hands before handling plants, and remove any stunted, mottled plants quickly. Do not use tobacco around peppers.Choose resistant varieties (many carry virus resistance), use clean seed, control aphids with reflective mulch and by conserving natural enemies, manage nearby weed reservoirs, wash hands and tools, and remove infected plants early. Avoid tobacco use around the plants.
Symptoms Plants suddenly wilt and die, often with a dark rotted patch on the stem at the soil line, and the fruit can rot too, sometimes with white fuzzy growth. It strikes in warm, soggy soil after heavy rain.Plants wilt and collapse suddenly, often with a dark, water-soaked lesion girdling the stem at the soil line, and roots rot; dark, firm, sometimes white-cottony rot also strikes the fruit. Caused by Phytophthora capsici, it flares in warm, wet, poorly drained conditions and after heavy rain or flooding, and can move fast through a bed. Cause A mold-like disease that lives in wet soil and spreads in splashing and running water, attacking pepper roots, stems, and fruit in warm, soggy conditions. It moves fast once it starts.Phytophthora capsici, a soilborne water mold that thrives in saturated soil and spreads in splashing and running water. It survives in soil and debris for years and moves fast in warm, wet weather, especially on heavy or poorly drained ground, attacking roots, crown, and fruit. Organic treatment Pull and destroy affected plants and fruit, and fix the drainage. There is no good home cure once it takes hold, so prevention is what matters.Remove and destroy affected plants and fruit promptly, and improve drainage immediately. There is no effective home-garden cure once plants collapse, so control is preventive and drainage-based. Prevention Plant on raised beds so water drains away, avoid wet low spots, do not overwater, water at the soil, and rotate peppers away from tomatoes, eggplant, and squash. Look for resistant varieties if this disease is common where you live.Plant on raised, well-drained beds, avoid low spots that stay wet, choose resistant varieties where available, water at the soil rather than overhead, mulch to limit splash, rotate away from solanaceous and cucurbit crops on a long cycle, and avoid overwatering, which is the single biggest trigger.
Symptoms Sunken dark spots appear on the peppers, especially ripe red ones, spreading into rotting patches flecked with tiny pink or black dots. It is worst in warm, wet, humid weather.Sunken, circular, water-soaked spots develop on the fruit, especially ripening red fruit, enlarging into dark lesions dotted with concentric rings of pink-to-black spore masses that rot the pepper. It is chiefly a fruit-rot disease, favored by warm, wet, humid weather, and can carry over on infected seed and debris. Cause A fungus that rots pepper fruit, spread by splashing water and carried on seed and old plant debris. Ripe peppers are hit hardest, especially in wet weather.Colletotrichum fungi that infect the fruit and are spread by splashing water; the pathogen survives on infected seed, crop debris, and volunteer plants. Ripe and injured fruit are most susceptible, and long warm, wet spells drive outbreaks. Organic treatment Pick off and throw away infected peppers right away, keep the fruit dry by watering at the soil, and harvest ripe peppers promptly instead of leaving them out in wet weather. Rotted fruit cannot be saved.Remove and destroy infected fruit promptly to reduce spore load, and keep foliage and fruit as dry as possible. Where the disease is active a labeled fungicide can protect healthy fruit, but rotted fruit cannot be saved. Pick ripening fruit promptly rather than letting it sit in warm, wet weather. Prevention Use clean seed and healthy transplants, do not plant peppers in the same spot for a few years, water at the soil, keep fruit off the ground, and clean up old plants at the end of the season.Start with clean or treated seed and healthy transplants, rotate peppers out of the bed for 2 to 3 years, water at the soil, mulch to limit splash, space for airflow, stake to keep fruit off the ground, and remove crop debris at season's end.
