How do I get rid of gnats that live in my house plants?

I recently re-potted my house plants and for some reason they are now infested with gnats. I have already tried a bugspray for houseplants but its not working. I heard of using Dawn dishsoap mixed with water does that really work? And does it have to be Dawn or will any dishsoap work?

How do I get rid of gnats that live in my house plants?
I've tried the soap (Ivory) spray, and it hasn't worked that well for me.





Chemical solutions:





Ortho Rose %26amp; Flower Insect Killer (recommended for houseplants); contains bifenthrin.





These insecticides that contain permethrin, pretty well known and not dangerous: Bonide Eight Garden %26amp; Home Insect Control, Southern Ag Garden Insect Dust, Spectracide Bug Stop Multipurpose Insect Control Concentrate .
Reply:The lemon dishsoap works well. You can spray on your solution or let them soak in the sink. I'd fill a large bowl with soapy water and dunk in the foliage, shake it out, dunk in again, shake, etc. the first time, and then make sure you have some of the solution (a tablespoon dish soap + spray bottle mostly full of water) on hand through the summer months to spray them once a month or so.
Reply:We have to flush/drown the plants in the tub a few times a year. . . It is the only thing that helps, plus keeps the salt levels down in you plants also :) GL!!!
Reply:These gnats are called fungus gnats. They breed in the soil, and they love peat moss because it holds water so well that fungus levels go up.





The chemical method is to use permethrin (which can be found in outdoor insect killers, check the label). It is used as a soil drench, but you only need to get into the first couple of inches of soil. This is a very toxic solution if you have fish or small pets. Keep the plant away from children and pets for 4 months.





There are several ways to manage them using "home remedies." Some of them are already mentioned. Here's a few more:





1. They don't like peppermint tea. You need to keep up the peppermint tea treatment for a while until their breeding cycle is broken. However, this means you may have to overwater the plant and that leads to fungus growth and root rot.





2. They absolutely hate cinnamon. The powdered cinnamon that you can find in a big container in any dollar store is a massive repellent for them. And it smells good to humans. This breaks their breeding cycle because they can't get to the soil to lay eggs.





3. Repot again, and this time, put 1-2 inches of clean sand (if you can't find this, look in an aquarium supply place) on the top of the soil.





4. Heat treat any soil you use to repot. Microwave it (directions below) This will stink, but it's better than gnats.





5. You can try freezing the soil before use if you have a big freezer. That's what I do to keep those grain-moths from appearing when I buy bulk grains from the health food store. But I never tried it on the soil.





Best wishes!