Properly cared for, the canvas material of a tent or pop-up camper will last for years. But if the tent is packed away wet and not properly ventilated, mold and mildew may form. Not only is mold unsightly and malodorous, but it may also cause respiratory irritation to individuals and damage the integrity of the tent material. All is not lost if you get some mold on your tent canvas. With a little bit of work you can get the material back in shape.
Prepare a mixture of household bleach and water, in a proportion of 1 cup bleach to 1 gal. water. Mix this in a plastic bucket, and then decant it into a household spray bottle. You can buy spray bottles new in the housewares section of your local store, or you can wash out and recycle a bottle such as a glass cleaner bottle.
Spread out your tent on a flat surface, like a driveway, so that you have access to the area to be cleaned. To protect the fabric from abrasion, you may want to lay down a painter's drop cloth or tarp first.
Spray your bleach-and-water mixture onto the spots you wish to clean. Scrub the area with a soft-bristled scrub brush until you've removed the mold. Rinse with clear water. Areas with extensive mold may need several applications.
Hang your tent up to dry over a clothesline or rope you've strung up for the purpose. When the tent is dry, set it up and let it air for a day or so. Then pack it up until your next trip.
