A 50-50 solution of white vinegar and water is an effective natural ant killer. Chalk and talcum powder prevent ants from entering a home. Citrus peels, cucumber peels, spices and coffee grounds are also used to eliminate ant populations.
Ants hate the smell of vinegar and will avoid countertops that are regularly wiped down with a vinegar-water mixture. A spray bottle of vinegar and water can be used to kill active ant infestations. Ants will not walk across a chalk line or through a pile of talcum powder, so these are natural ways to keep ants outside. Place bay leaves, cinnamon, black pepper, cloves or garlic in drawers and pantry cabinets to ward off ants. Ants that find and eat a blend of borax and sugar will wander away and die. The blend can be hazardous to people and pets, so do not use a borax-sugar mixture where kids or pets will find it.