Summary: Pepper Integrated Pest Management Options

The key to prioritizing chores and the many possible IPM management options that might be used on your farm is to realize that there are five major pepper pests that must be dealt with annually. On most farms, there are also one or two occasional or minor pests that must be managed most years. The most successful growers design their pest management plan around these chronic problems and implement the solutions as part of their standard operating procedure.

The major pests include:

  • Weeds (as a group, but especially hairy galinsoga in pepper production)
  • Phytophthora blight (whether or not it is present)
  • Bacterial leaf spot (BLS)
  • European corn borer
  • Aphids (usually the green peach aphid)

An example of a pest that does not occur every year or at all locations, but must be included in your management plan if it is present on your farm, is the pepper maggot. Growers should construct a similar list of management options from IPM literature and manuals for other minor pest (i.e. Pythium) or abiotic disorder (e.g. bloom end rot, sun scald or blossom drop) that dramatically limit production and profits on their farm. Proper pest/damage identification is crucial before this process begins. Consult Extension IPM specialists or diagnostic laboratories for proper identification to avoid wasted efforts.

Major pests:

1.Weeds. All farmers must successfully manage weeds to produce a pepper crop, particularly, during the first 10 weeks after transplanting.

  • Galinsoga seeds are relatively short-lived in the soil. Rotate to fields where triazine herbicides were used in previous years (i.e. on sweet corn or tomatoes).
  • Eliminate the perennial, solanaceous weed, horse nettle, using late-season applications of glyphosate.
  • Select sites with lower populations of solanaceous weeds such as black nightshade that will not be controlled by herbicides registered for use on peppers.
    • Management options include:

      • Cultural controls
        • banded or liquid fertilizers
        • scouting
        • site selection
        • weed-free cover crop seed
        • cleaning soil from plows and cultivators between fields
        • rotation
        • smother crops
        • low or no-till
      • Mechanical controls
        • plastic or organic mulches
        • cultivation
      • Chemicals
        • pre- and post-plant herbicide applications
      • Or some combination of these.

      2. Phytophthora blight. This is the toughest pepper pest to manage, and can kill all plants in a wet year once established. Phytophthora is forever; there is no cure. All management plans must attempt to prevent the introduction or further accumulation of spores in the soil, and limit destruction if they are already present at high levels. Phytophthora requires 24 to 48 hours of soil saturation (standing water) to start the disease cycle. Water management is crucial in preventing this disease and minimizing its destruction.

      Whether or not Phytophthora is present on your farm all growers should:

      • Use a three-year crop rotation that does not include other solanaceous or cucurbit (vine) crops.
      • Select a site with good soil drainage.
      • Avoid planting low, wet holes prone to flooding.
      • Create swales or drainage ditches to remove water from fields.
      • Break up plow pans by V-ripping or chisel-plowing every few years.

      If you already have moderate to high levels of Phytophthora on your farm:

      • Use only Phytophthora-resistant varieties in infested fields.
      • Plant on dome-shaped, raised beds.
      • Create channels to remove water between beds and break beds in low areas to allow excess precipitation to leave the field.
      • Chisel-plow between beds during the season to allow water to penetrate rather than stand.
      • Hand or mechanically rogue infected plants or areas, during the season, to prevent aerial spread of spores.
      • Clean soil from plows and cultivators between fields; work infested fields last.
      • Use fungicides to limit spread.

      3. Bacterial leafspot (BLS) . This is the most common disease of peppers and can be very destructive during prolonged periods of hot, humid weather. Defoliation, leaf and fruit spotting, and delayed and reduced yields are common symptoms.

      • Use only BLS-resistant plants unless planting chili or sweet pepper types where resistance is not yet available, or the field is infested with Phytophthora (see previous pest).
      • Use a three-year crop rotation.
      • Choose site with good air and soil drainage; avoid foggy locations, if possible.
      • Control solanaceous weeds.
      • Hot-water treat seeds.
      • Produce and use clean transplants
      • Inspect and reject infected seedlings, if purchased.
      • Maintain proper pH and fertility levels.
      • Minimize leaf wetness time when irrigating or use trickle.
      • Do not work field while foliage is wet.
      • Scout plants weekly to detect disease in early stages.
      • Rogue plants in initial area of infection
      • Work infected areas last, to slow disease spread.
      • Spray susceptible varieties with copper bactericide if disease is detected.
      • Avoid using high-pressure air-blast sprayers that wound and infect plants and spread disease.
      • Lengthen spray interval by one day for each night below 60 oF.
      • Discontinue spray schedule once the temperature is below 60 oF on most nights during late summer.
      • Disk or plow after final harvest to hasten decomposition of crop residue.

      4. European corn borer. Attacks fruit at almost all sites annually. Most common cause of fruit soft rot. ECB management plan should take into consideration unintended effects on other insect pests.

      • Monitor for second-generation moth flight using two Scentry Heliothis traps, baited with either the NY (E) or IO (Z) pheromone lures, and placed in the tall weeds on the edge of field.
      • Initiate insecticide applications one week after combined trap capture > 7 moths per week.
      • Use selective/microbial insecticides to preserve beneficial arthropods, if possible.
      • Alternate between insecticides to prevent pest resistance.
      • Discontinue spraying one week after < 21 moths are captured in traps.

      5. Aphids. Aphids are induced secondary pests on peppers, usually caused by early or frequent use of broad-spectrum chemical pesticides (both insecticides and fungicides).

      • Preserve natural enemies by
        • delaying and minimizing pesticide use for other pests through the use of scouting, monitoring, action thresholds, and the use of alternative management strategies.
        • using selective/microbial pesticides for other pests whenever possible.
      • Use of plastic mulches (especially reflective silver) reduces aphid populations.
      • Scout 4 leaves/plant, 25 plants/field, weekly.
      • Spray
        • prior to fruit set if you find an average of 5 to 10 aphids/leaf for > two weeks,
        • immediately after fruit set if more than 5 aphids/leaf.
      • Alternate between insecticides to prevent pest resistance.

      Occasional pest(s):

      6. Pepper maggot. Not on all farms, but very common in coastal states south of the MA/NH border. It is essential to determine if this pest is present on your farm before switching to a reduced or microbial insecticide program. At present, there are no selective materials available that will control or suppress this pest. Sprays must be targeted to control the adult fly before and during the oviposition (egg laying) period. Alternative methods are available. Another common cause of fruit soft rot.

      • Seek professional help to determine if this pest is present on your farm prior to switching to an IPM low-spray system or while making the change from a calendar-based, cover spray program. Or,
      • Rotate to a distant off-farm location where it is certain that PM does not exist.
      • Eliminate the alternate host, horse nettle, from fields and borders.
      • Plant peppers as far from most trees and woodlines/hedgerows as possible.
      • Plant two rows of trap crop (hot-cherry peppers) all around field with a wider barrier (i.e. 20-30 feet wide) between any woodline and main crop of bells, etc.
      • Monitor through July and early August using liquid ammonia-baited, yellow sticky traps, at the height of 20 feet, within the canopy of a nearby tree (i.e. maple). Or,
      • Monitor oldest fruit on indicator plants (hot-cherry peppers) in border rows for shallow surface depressions (indents) with tiny round oviposition scars during early and mid-July.
      • If using trap crop, either do not spray for PM, or treat only the border (cherry-peppers) after the first adult fly is captured or oviposition scars begin to appear on fruit. This will preserve beneficials on main crop.
      • If not using trap crop, spray all peppers after the first adult fly is captured or oviposition scars begin to appear on the fruit of indicator plants.
      • Discontinue spraying after 1-3 applications/weeks that covers the period of fly emergence and oviposition.
      • If spraying was necessary, scout for aphid outbreaks due to loss of beneficials (see previous pest).

      7. Create your own list(s) for other minor pest(s) limiting profits and/or production on your farm.

      By: T. Jude Boucher, Vegetable IPM Coordinator, University of Connecticut Cooperative Extension System. Reviewed 2012.

      This information was developed for conditions in the Northeast. Use in other geographical areas may be inappropriate.

      The information in this document is for educational purposes only.  The recommendations contained are based on the best available knowledge at the time of publication.  Any reference to commercial products, trade or brand names is for information only, and no endorsement or approval is intended. The Cooperative Extension System does not guarantee or warrant the standard of any product referenced or imply approval of the product to the exclusion of others which also may be available.  The University of Connecticut, Cooperative Extension System, College of Agriculture and Natural Resources is an equal opportunity program provider and employer.