First, check out this article about removing mold from canvas tents.1. Dry-scrub the area with a soft bristle brush or sponge.  2. Kill the mold with a mixture of 1-part white vinegar (distilled) to 3-parts water.  Spray it on and let it dry.3. Use Iosso Mold and Mildew & Stain Remover.  This is our go-to product.  It is gentle on canvas and has historically done the best job. Follow the on-pack instructions.  Try spot cleaning with a hot-water mixture in a spray bottle, or create a solution in a bucket and apply with a sponge. Don’t be alarmed if all of the mold hasn’t been removed yet.4. Let it dry in direct sunlight.5. Apply another treatment and let dry. You may need to repeat this a third time.6. Rinse and let dry before storing.**NEVER USE BLEACH**