Black ants often seek the moisture and food morsels founds inside a dishwasher. The tiny insects are capable of entering through the drain or vents. An acidic household cleaner that often is used to make homemade black ant insecticide also is an effective dishwasher scouring powder. A hot wash cycle with this dual-purpose cleaner kills ants inside the dishwasher and sends them out the drain. Get the black ants out of a dishwasher with a boric acid flush.
Empty all the dishes from the dishwasher. Hand wash the dishes to avoid transferring ants to the counters.
Divide 1 cup of boric acid powder equally between the soap dispensing reservoirs in the dishwasher door. Close the dishwasher door.
Set the dishwasher to run on the hottest and longest wash cycle possible. Open the dishwasher to see if any living ants remain. Add another cup of boric acid and cycle the dishwasher a second time if any black ants are found.
Run the dishwasher empty on a hot rinse cycle with no boric acid or soap inside. The final rinse clears out any remaining residue from the acid and flushes the drain. Now the dishwasher is free of black ants and ready to use again.
Boric acid can be used to deter ants from entering the dishwasher. Dissolve 1 tbsp boric acid and 1 tsp of sugar in ½ cup warm water. Soak cotton balls in the solution and place them behind and beneath the dishwasher.
Boric acid may cause skin irritation. Wear rubber kitchen gloves when handling the acid.