These remedies will help remove stains on wooden decks or porches.
Stain Remedy Mildew Clean the surface with a commercial deck cleaner/brightener. If it is not in liquid form, mix the powder concentrate with the recommended amount of water and apply with a garden sprayer, brush, or roller. Wait several minutes, then brush briskly with a stiff brush or broom. Rinse with a garden hose. Some cleaners may contain acids or chlorine, which can harm plants; check your label. Candle wax Saturate a rag with mineral spirits. Set the rag on the dried wax until it absorbs the wax. You may rub lightly. Barbecue stains (including grease and sauce) Scrub with a strong household detergent or water-rinsable automotive degreaser or carburetor cleaner. Rinse the area before it dries. Tannin Remove the black streaks of tannin-rich woods with a specially formulated tannin cleaner. Rust Apply a solution of water and 5 percent oxalic acid to the stain. Let it sit for several minutes, then rinse. Leaf stains Spot-scrub the area with a 1-to-1 solution of household bleach and water. Green algae or moss These stains are difficult to remove and usually reappear once the roots are formed in the wood, but you can temporarily eliminate them by scrubbing with a solution of 4 parts bleach to 1 part water. Sap Scrape excess material with a putty knife or steel wool. Wipe with turpentine.
Try these cleaning tips for patios with a stone or cement surface.
Stain Remedy Food, grease, oil, lipstick Mix dishwashing detergent in warm water. Work the mixture into the stain with a stiff brush or broom. Don't skimp. Rinse with clean water. If this doesn't work, add ammonia to the detergent and water mixture, following the same rinsing procedures, or scrub well with mineral spirits. Paint and candle wax Remove all the paint or wax you can with a regular or putty knife. Scrub the area with a metal-bristled brush and cold water. If this fails, apply mineral spirits to the area. If the stain is on concrete and these treatments don't work, try aluminum oxide abrasive or an abrasive brick. Blood, coffee, juice, feces Use dishwashing detergent in cold water. Remove the stain as soon as possible. Work with a stiff brush or broom, and flood the area with the detergent mixture. Rinse with clean, cold water. Tar and heel marks Try dishwashing detergent in warm water. If you're unsuccessful, scour the area with a stiff-bristled brush and mineral spirits. Don't use a scouring pad. If some residue remains, flood the area with mineral spirits and blot it up with a soft absorbent cloth. This may take several applications.
Efflorescence Rub the area with a wire brush. This should remove the white stain, which is caused by salts in the masonry mixture. If this doesn't work, many commercial stain removal mixtures are available that will remove the stain. They contain an acid, so be sure to wear gloves and safety glasses. Dirt and grime Hose down the surface with water and scrub it with a stiff broom. If this doesn't work, mix dishwashing detergent or trisodium phosphate with warm water and go over the area with a stiff brush or broom. Soot Apply detergent and water. If this doesn't work, apply a 1:1 mixture of muriatic acid and water. Be sure to wear gloves.