Mildew, mold and leaf stains on marine vinyl, boat upholstery or leather furniture often cannot be completely cleaned, but they can be concealed with Rub ‘n Restore®. These stains must first be treated to kill any living fungus, so it does not grow through the new finish.
For leather, treat mold or mildew with denatured or rubbing alcohol (high proof vodka or Everclear are even better). Alcohol is better than undiluted distilled white vinegar due to its less acidic pH. It also leaves less odor. Allow to sit for 30 minutes to several hours and then gently scrub the surface.
For marine vinyl, we’ve had many years’ success with a solution of 10% bleach in water, but EPA and OSHA (and certified mold inspectors) have retracted bleach as an effective mold remediation. Bleach is no more effective than alcohol or distilled white vinegar but is more toxic. It does, however, work faster (let it sit only a few minutes and wipe dry). It also lightens the remaining stains most effectively. Some customers have also reported success with Marine 31® Mildew Remover.
Never use abrasives like borax or baking soda on leather or vinyl.
If the mold is present on the interior stuffing, if it returns after treating the leather or vinyl, or if you’re concerned about mycotoxins, the items should be placed in a sealed ozone chamber. Contact a local fire or flood restoration company. Otherwise, the piece will require replacement or reupholstery.