Remove any peeling or flaking paint from the wood, if applicable, using a paint scraper. Mildew can thrive underneath loose paint, as well as on exposed wood.
Wet any plants, shrubs and grass near the fence wood with water to protect them from the trisodium phosphate runoff.
Fill a bucket with 1 gallon of warm water. While wearing rubber gloves, thoroughly mix 10 tbsp. of trisodium phosphate and 1 cup of chlorine bleach into warm water.
Dip a nylon bristle brush into the trisodium phosphate and bleach solution. Scrub the fence wood with the nylon bristle brush and solution until the green mildew is completely removed.
Rinse the wood with fresh water to wash away the solution. Allow the wood to thoroughly air dry in the sunlight.
Apply two coats of mildew-resistant paint to the wood using a paintbrush. Let each coat of paint air dry according to the paint manufacturer's instructions.
Things You Will Need
- Paint scraper
- Garden hose
- Rubber gloves
- 10 tbsp. trisodium phosphate
- 1 cup chlorine bleach
- Nylon bristle brush
- Mildew-resistant paint
- Substitute washing soda for the trisodium phosphate.
- Remove severe mildew stains with a solution of 3 tbsp. oxalic acid and 1 pt. water. Wear protective gear while handling the solution, since oxalic acid is poisonous. Thoroughly rinse the wood when finished cleaning with oxalic acid.