Fruit flies Flies are among the most common and annoying home pests. We’ve put together a guide to the most common flies that invade your home. Learn how they end up there and what you can do about them.

Housefly

  • Gray tone, up to one-half-inch long
  • More common indoors during warmer months, but can survive up to 50 days indoors if food is present
  • Carries many disease-causing germs
  • Tends to rest in room corners or on thin objects, such as blinds or electrical cords
  • Prevention tip: Maintain a clean house. Dispose of pet waste properly. Seal garbage cans tightly. Install screens over windows and doors and be aware of other common insect entry points.

Cluster fly

  • Large, dark gray, slow-moving flies. These are the flies that bump into you in winter
  • Tend to cluster along window ledges and are more prevalent on the upper floors of a building
  • Are earthworm parasites; commonly found where healthy earthworm populations exist, such as in a well-groomed lawn
  • Don’t reproduce or feed during winter
  • Prevention tip: Apply an insecticide perimeter treatment to exterior walls, especially warmer southern and western walls. Treat upper floors, since flies tend to gather there.

Blowfly

  • Fairly large flies in shades of metallic green, blue or black
  • More common during warm months, although sometimes adults overwinter inside walls and emerge into warm living spaces
  • A scavenger fly associated with pet waste, manure or dead animals
  • Prevention tip: Keep garbage cans tightly sealed; dispose of pet waste properly.

Fruit fly or vinegar fly

  • One of the smallest flies found indoors, around one-eighth of an inch
  • Typically enter homes during fall harvest season, when outdoor populations are high due to ripening fruits
  • Prevention tip: Remove overripe fruits and vegetables. Rinse recycling materials to eliminate bits of soda or beer, which can ferment and provide breeding areas for fruit flies.

Fungus gnat

  • Small, black-colored fly (up to one-eighth of an inch) often seen buzzing along windows and near houseplant soil when you water
  • Larvae feed on fungus and organic matter, including plant roots, in potting soil
  • Frequently enter homes in fall when houseplants are brought indoors after spending the summer outside
  • Prevention tip: Reduce watering frequency for houseplants and allow soil to dry between waterings. Don’t let plants sit in water; don’t allow water to sit in drainage dishes. For severe outbreaks, use Bayer Advanced 12 Month Tree & Shrub Protect & Feed II.