Remove the cushions from the furniture. Wipe the surface mold off the cushions using a damp cloth. If the cushions have washable covers, remove the covers and launder as you normally would, but add 1 cup of white vinegar to the water. Continue with the remaining steps if the cushions do not have washable covers.
Fill a clean spray bottle with undiluted white vinegar and spray it onto the front and back of the cushions. Allow the vinegar to sit on the cushions for 10 minutes.
Mix 3 cups of warm water with 1 tsp. of liquid dish soap. Saturate a sponge in the mixture and scrub the front and back of each cushion.
Rinse the cushions by wiping them with a clean cloth dampened with cool water. Allow the cushions to air-dry.
Spray the outdoor cushions once again with the white vinegar. The vinegar will kill any remaining mold spores while removing any lingering odors. Allow the vinegar to air-dry on the cushions.