As with any other type of stain, stains on your concrete countertop should be removed as soon as possible. The longer a stain is left untended, the further it can migrate into the concrete, making removal increasingly difficult.
Generally, a bit of water and a mild dishwashing soap will take care of most stains. We recommend applying the mixture with a spray bottle set for misting. Spraying water under pressure may push the stain deeper into the concrete.
For more difficult stains, a poultice mixture made up of fine powder and a solvent can be used to draw out the stain from the concrete surface. While any number of ingredients can be used, we recommend using flour and a few tablespoons of hydrogen peroxide. The consistency you are looking for should be similar to peanut butter. Let the paste sit for a full 24 hours in order to give the mixture adequate time to bring the stain to the surface. Once dry, wipe away the mixture and scrub the stain.
Etching created by acidic liquids like lemon or orange juice can be removed with a fine-grit sandpaper. If the countertop was previously sealed, the surface should be resealed with the original sealer according to the manufacturer’s instructions. If your countertop arrived unsealed, you may want to consider purchasing a countertop sealer to prevent future staining or etching.
Concrete countertops can be found in Barkman’s Outdoor Kitchen Kits. When cleaning a countertop installed by a manufacturer other than Barkman, it is recommended that you consult their own product literature for further cleaning tips.