Because wood counters are naturally porous, when it is used as a food preparation surface it is very important to clean it thoroughly after each use. A mild soap like liquid dish detergent and water works well. Dry with a towel or other soft cloth. If you prefer, use a bleach and water solution to help kill bacteria. (Mix a tablespoon of bleach with about 1 gallon of water. Keep the solution in a clearly marked spray bottle out of the reach of children.) You may also be able to remove stains by soaking the area with lemon juice for a few seconds. Avoid using cleansers which would be considered toxic as it will be absorbed into the wood.

Hardwood countertops used as work surfaces and cutting boards have a penetrating oil finish. To maintain, periodically apply a non-toxic oil formulated for kitchen use. Treatment may be needed if the wood begins to dry out, lightening in color – especially where pieces are glued together.

Some hardwood countertops not used for chopping or other food preparation are treated with varnish. These surfaces do not need oil treatments. Countertops that are finished with polyurethane can be washed with mild soap and warm water, then wiped with a dry cloth. Polyurethane-finished hardwood is not to be used as a cutting surface because knives will cause permanent damage.

You can sand your countertops to remove scratches and knife marks to restore the surface. Use 100 grit sandpaper to remove heavy damage following up with 120 grit and 220 grit in sucession, if the wear on the surface is mild you can start with 120 grit and proceed to 220 grit. Don't use anything finer than 220 grit as the finer the grit you use the tighter the pores in the wood will be which would inhibit the absorption of the oil finish.