Foam cushions can become dirty and smelly. Avoid the temptation to unzip the covers and toss the cushion in the washing machine. Machine laundering can cause irreparable damage by shrinking or fading the cushion. There is a way to clean and remove odours without harming the cushion and its cover.
Place cushion in a shady area outdoors for one to two hours. This will eliminate most odours.
Mix one-quarter cup of carpet/upholstery cleaner and one gallon of water in bucket. Vigorously agitate to create a foam layer. This can be substituted with a foaming carpet/upholstery cleaner.
Spread the foam over small areas of the cushion. Test for colour fastness on a small inconspicuous area first. Avoid rubbing too hard or allowing liquid to seep into the cushion. Chemicals and water can break down the composition of the foam rubber.
With a damp cloth or sponge, wipe every area that has had cleaner applied. Rinse cloth or sponge frequently to remove the cleaning foam. Repeat until all cleaning solution is removed.
Place in a shaded area outdoors to dry completely. Turn over as needed to allow equal drying of both sides.
Use gloves, especially if you have sensitive skin. Work on cushion in area that will not be harmed by any dripping or spills of cleaner.
Test small area of cushion for colour fastness before continuing. Follow all safety precautions on carpet/upholstery cleaner container.