I am in the country, and ants are my arch enemies.  Around my little guys food bowl I use cinammon, they hate the smell, and just sprinkle it all around his placemat ( I also sprinkle it around my cabinets, and anywhere else the ants like to go marching--you need to reapply about every week to keep the smell going though).     
A great nontoxic (and cheap) way to get rid of the ants outside is to bring a gallon of water to a boil and pour it directly on the ant hills and all around the area.  You may have to use a few gallon if they are over an extensive area.     |