Fruit Fly

Symptoms by part

Causes

• Overripe or decaying fruit left on the plant or ground.
• Open wounds or cracks in the fruit skin that provide easy entry for egg laying.
• High humidity and warm temperatures that speed up the life cycle.

Could be confused with

• Fungal rot · Fungal rot typically shows fuzzy mold growth on the surface, whereas fruit fly damage shows internal tunneling and larvae.
• Bird damage · Bird damage creates larger, jagged tears in the skin rather than the tiny, precise pinprick holes left by fruit flies.

Treatment

1. Pick all ripe fruit immediately to remove the food source.
2. Collect and dispose of any fallen fruit from the ground every day.
3. Place infested fruit in a sealed bag and dispose of it in the trash, not the compost pile.
4. Apply spinosad to the foliage and fruit surface to deter egg laying, follow the label.

Without chemicals

• Bag individual fruits with fine mesh netting or paper bags while they are still green to prevent access.
• Use yellow sticky traps near the canopy to catch adult flies.
• Set out small containers filled with apple cider vinegar and a drop of dish soap to attract and drown adults.

Chemical options

• Spinosad, apply as a spray to the fruit surface during the ripening phase, follow the label.

Preventing it

• Harvest fruit as soon as it reaches maturity.
• Keep the area beneath trees and shrubs clear of all dropped fruit.
• Prune branches to improve airflow and reduce the humidity levels that attract flies.
• Use exclusion netting over entire bushes or small trees before fruit begins to ripen.

When to act

Act as soon as you see the first puncture marks on your fruit. If the infestation is widespread and the majority of the crop is soft or rotting, remove the fruit entirely to stop the cycle for next season.

Questions people ask

Can I eat fruit that has been visited by a fruit fly?

It is best to discard fruit with puncture marks because the larvae are likely already feeding inside, which causes rapid decay.

Will my compost pile attract fruit flies?

Yes, if you add infested fruit to a compost pile, the larvae can complete their life cycle in the soil. Always bag and trash infested fruit instead.

Plants it affects

• Blueberry
• Feijoa
• Papaya
• Starfruit