Ants are probably the most common pest in homes everywhere in the country. There are many species that will invade homes and control measures for one species may not work for another. In NM, for instance, we have approximately 226 species of ants, more than in all of Europe, so ants are a problem in many homes. Below in the comment section are some non-toxic methods of dealing with them
If you know where the ants are coming in from, you can repel them with such products as food-grade diatomaceous earth (DE), baking soda, talcum powder, medicated body powder, damp coffee grounds, salt, cayenne or garlic powder. Place any of these materials in corners, under baseboards or in any cracks and crevices where you see ants emerging. These products are mostly powders and won’t work around the perimeter of your home as they will be blown away or washed away.
If you can find the ant’s entrance on the outside you can block it with Vaseline Petroleum Jelly, any toothpaste or duct tape. You can also squeeze the juice from a lemon into the opening and leave the lemon peel there. You can spray the ants themselves with a mixture of 40% water, 40% alcohol and 20% dish soap (these proportions don’t have to be exact).
If you have ants making mounds in your yard you can flood the nests with club soda, a dilution of orange juice, Lemon Joy, and peppermint or with white vinegar or food-grade DE. If you use the DE, mix 4 tablespoons per gallon of water. You can also use 1 gallon of orange juice diluted with 2 gallons of water and a dash of soap. If you prefer, you can also spread dry instant grits on the mound. The ants will eat it and not be able to digest it and die. Another method for dealing with ant mounds requires baking soda. Sprinkle baking soda on a damp mound (about 1 – 2 cups), wait 30 minutes or so and pour a cup of vinegar on the ant hill. The combination is deadly to ants.
Once ants are in the house you can usually eradicate them with a least-toxic bait. However whether it is least-toxic or not I always recommend placing baits where children and / or pets cannot get to them. One bait that works on many species is a mixture of 2 tablespoons each of peanut butter and jelly with 1 tablespoon of boric acid or Borax. A good commercial bait for ants is Terro Bait, which is made from boric acid.
When you use baits the ants will take it back to the colony and kill the queen. If you are seeing dead ants around the bait, they aren’t taking it back and the problem won’t be solved. You may want to change baits if this is a problem.