Fruit flies are attracted to rotting or fermenting fruit. They will also breed in this decaying fruit. Therefore, the first and most obvious preventative measure is to avoid having any rotting fruit lying around in your home, or in your garden. If you have fruit trees outside, keep up a regular schedule of swiftly disposing of any fruit that has fallen to the ground. People who live in more humid areas are more likely to have problems with fruit flies in their home.
Fruit flies might be accidentally brought into the home on fruit that you have bought or picked, or you may have brought fruit in that had fruit fly eggs on them. This is the start of the cycle of fruit fly infestation that must be broken. Because fruit flies have such fast life cycles of around eight days, it does not take long for their numbers to increase to plague levels if left unchecked.
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