If you don't want to do combat with commercial pesticdes, there are many easy, safe and effective alternatives.
Here's some tried and true methods against common pests. Ants: Spread cinnamon, bay leaves, cayenne pepper, salted cucumber peels or leaves from mint tea bags near their point of entry or along baseboards. Mice: Place cotton dipped in peppermint oil near problem areas. Mosquitoes: When you barbeque, throw some sage or rosemary onto the coals. Carpenter Ants: Mix 3 cups hot water, 1 cup sugar and 4 teaspoons boric acid. Soak cotton in the mixture and leave it near places where ants are found.