Pour vegetable or olive oil in your kitchen sink. This will catch any gnats that hang around the drain or garbage disposal. The gnats will fly into the oil but will be either unable to free themselves from it, or simply unable to mate afterward, as they are coated in the oil. You may need to repeat this process several times to get all of the gnats, but it is very effective.
Today the guy who sprays my house was here. I told him I had a lot of what looked like gnats, but there was no food out. He said: buy a bottle of degreaser and pour it for sure in both your kitchen sink drain before you go to bed. Then in the morning before you put any water down the drain pour very hot water in each drain. Gnats fly down to the gunk in your J pipe lay their eggs and a new crop hatches over night. Repeat nightly until your gnat problem is gone.
How to Rid of Annoying Fruit Flies and Gnats in the Kitchen
Does it seem like summer bring a swarm of fruit flies and other nasty flying creatures in your kitchen, either messing with all of your ripening fruit or in your drains? Here are some ways to get rid of those pesky little creatures...
Our trick for getting rid of fruit flies is simple: put three drops of dish soap (whatever kind you use) into 1 cup of vinegar and leave it out in a bowl. The vinegar will attract the flies to the bowl and the soap will reduce the surface tension so the flies sink to the bottom.