Gnats are frustrating little insects. They hang around your houseplants in swarms, fly in your face as you walk by and occasionally drown in your drinks. They are too small to swat. And no one wants to douse their house in pesticides unless absolutely necessary. Luckily, you can kill household gnats with a little rubbing alcohol. A few applications will kill the population of fungus gnats in your home and allow you to enjoy your plants in peace.
Mix one cup of rubbing alcohol with one quart of water.
Stir the mixture well and add it to a plastic hand spray bottle.
Coat your plants' leaves with the spray. Approach the plant slowly so as not to disturb the gnats. Early morning, just before sunrise, is the best time to surprise them. Spray the plant thoroughly to coat all of its leaves just before the point of runoff. Try to hit some of the fleeing gnats with the alcohol spray too.
Re-spray the plant at three-day intervals until the gnat population is dead.