Borax contains boric acid, a substance that is toxic to roaches. When a roach comes into contact with Borax, the powdery substance sticks to the insect's body. As the roach cleans itself, it ingests the powder and dies within a short period of time. Sprinkling a mixture of Borax and sugar in high roach traffic areas helps to attract multiple roaches because they are drawn to the sweet smell.
When treating the entire home for roaches, Borax should be sprinkled on baseboards, countertops, inside cabinets and behind kitchen appliances. It is best to treat the areas at night because roaches tend to be more active in the dark. Boric acid is not considered toxic to humans, but it is still important to take safety precautions when sprinkling the powder to ensure that it is not inhaled.
Additional home remedies for roaches include catnip and diatomaceous earth. Catnip contains nepetalactone, a substance that is safe for humans and pets but toxic to roaches. Catnip can be sprinkled in high-traffic areas or mixed with warm water spray throughout the home. Diatomaceous earth is a powdery substance that is not toxic to humans. When applied to areas where roaches congregate, the insects ingest the powder and typically die within 48 hours.