Boric acid is a naturally occurring compound found in fruits, vegetables, water and soil. Another form of boric acid is boric acid crystals, which come from dried salt lake beds. Boric acid has many uses and is commonly mixed with water for use as a pesticide or fungicide.

Step 1

Fill a 16 oz. spray bottle with water and add 1 tbsp. of boric acid. Screw the lid back on the bottle, and gently mix the solution by turning the spray bottle upside down and then right side up again. Do this three or four times.

Step 2

Spray the boric acid and water solution on dry rot, insects, fungus, or mold. Let the boric acid solution dry, and remove any residue that is visible with a cloth if the boric acid and water solution has been applied to counter tops or any other exposed surfaces.

Step 3

Store the boric acid solution in an area that is out of the reach of children and pets. Boric acid is a stable solution and can be stored at room temperature.