Decks become stained with dirt, mold and even food stains like olive oil. The problem with olive oil is that it soaks into the wood of your deck or adheres to the finish of a composite deck. It is difficult to remove, but, if treated as soon as possible, you can beat the odds and clean the olive oil off your deck. First test any cleaning method used in an inconspicuous spot on the deck to ensure it does not discolor or damage the decking.
Fill a bucket full of hot water, and scrub the olive oil stain off with a stiff bristle scrub brush for wood decks and a soft bristle brush for composite decks. To prevent burns use water that is no hotter than 120 degrees F, according to the U.S. Consumer Product Safety Commission. Rinse with hot water to wash the stain away.
Add about 1 tbsp. of dish detergent labeled to cut grease for every gallon of hot water. Use a bristle brush to get the oil stain clean. The dishwashing detergent helps to bring up and trap oil. Rinse the olive oil away with hot water.
Scrub some grease-removing cleaner, such as one used for automobiles, onto the olive oil with a bristle brush. Read the label to ensure you can rinse the grease-removing cleaner with water. Rinse it clean with hot water if applicable.
If the olive oil stain is difficult to remove, soak a paper towel in mineral spirits and dab it on the olive oil-stained deck so it soaks into the stain. Let it sit for about 10 or 15 minutes, and rinse it clean with hot water.