Damp conditions — or even maintaining a futon mattress on the ground without ventilation under it — may lead to unpleasant musty scents on the bed. Eliminate the musty odor by airing the mattress out, ideally in a sunny location, and sprinkling it with baking soda. Discard the mattress if it shows significant mold or mildew, because this isn’t easy to remove completely and may be a health issue.
Fresh-Air Odor Remover
Cart the futon mattress outdoors, and prop it up against a pole or in any place where the two sides can receive significant airflow. Mustiness is a indication that the mattress was damp or wet; even sweat and humid atmosphere can cause it to absorb moisture. If you can’t take the mattress outdoors, prop it up inside in a well-ventilated area and aim a fan at it, or turn to a fan. In case some mildew spots are present, brush them off using a soft scrub brush while wearing a mud mask. Afterward, rest the bed on its framework or a flat surface and sprinkle baking soda on it. Vacuum the baking soda off after 30 minutes approximately. Then flip the bed and repeat the process. Maintain the futon mattress on its own futon frame or a slatted platform bed to keep it dry, which prevents mustiness. Spritz a small amount of vinegar to any mildew spots while airing the mattress out.