Usually every other year or so, we clean the upholstery below. Luckily because of the upholstery we chose, it doesn't show dirt and is still in great shape 6 years later, but when you live on a boat, it absorbs salt from the sea air and eventually starts feeling damp all the time. At that point, we strip the covers off all the cushions and launder them. We turn them inside out, and launder in cool water and hang to dry -- no dryer even on fluff because if they shrink one iota, we'll never get them back on!
I remember the first time we decided something had to be done with the upholstery. We were in the Rio Dulce, Guatemala and there is no such thing as a dry cleaners.... I was fairly certain that they had to be dry cleaned (having lived in corporate america forever in a prior life), but with no dry cleaner available, I chanced laundering them in cool water for the first time. To my surprise, they turned out great!
And it's a lot less expensive than to have a professional upholstery cleaner come to the boat or to take them to the dry cleaner! If you decide to try this, be sure to test one before plunging into washing all your upholstery just in case you have different material that doesn't tolerate this approach!
It seemed like a good time to do it since we still had the condo the kids stayed in for an extra couple of days ... voila, washer and air conditioned location to dry the covers! :) Now they smell fresh and even though they don't look any different, they don't feel damp anymore!
More on what we do to put the boat away for hurricane season in future installments!