Boat Mildew Removal & Prevention

How to Prevent Mildew on Boat Seats and Canvas

A boat under a cover or sitting on a lift is basically a greenhouse for mold. Dark, damp, no airflow for weeks at a time. That's why mildew shows up on seats, cushions and canvas even on boats that get washed regularly.

Killing an outbreak is the easy part. Keeping it from coming back every few weeks is what actually saves your vinyl, because every round of scrubbing takes a little more life out of the surface. This collection covers both jobs: the dedicated remover for active mildew, and the everyday products that keep it from taking hold again.

Stopping Mildew Before It Starts

Mildew needs moisture and still air. Take either one away and it struggles to establish.

• Dry the boat before you cover it. Throwing a cover over a wet interior traps the humidity in with the vinyl. Ten minutes with a towel beats an hour of scrubbing in July.
• Give it airflow. Crack a vent, prop a cover corner, or run a passive moisture absorber in the cabin. Still air is what lets spores settle and grow.
• Get cushions off the floor. Water collects there. Stand them on edge or pull them out entirely for long storage.
• Empty the lockers. Damp towels, life jackets and ropes stored wet will seed mildew into everything around them.
• Clean the cover, not just the seats. Canvas holds moisture longer than anything else on the boat, and mildew growing on the underside of a cover drops spores straight onto the upholstery.
• Wipe vinyl down regularly. A boat interior cleaner used every few trips keeps surfaces sealed and drier, which gives spores far less to grab onto than bare, sun-dried vinyl.

Cleaning Mildew Off Canvas, Covers and Vinyl

Bleach kills mildew, then eats your vinyl and stinks up the cabin for a week. Regular soap doesn't touch it. Boat Juice Mildew Stain Remover breaks the mold down at the source and lifts the stain out instead of bleaching it lighter, with a Mango Tango scent instead of a chemical one.

1. Spray the product directly onto the mildew or mold stain.
2. Let it dwell for 30 seconds to 2 minutes, and don't let it dry on the surface.
3. Wipe clean, using light scrubbing on tougher spots.
4. For stubborn or set-in stains, a second application is normal.
5. Follow up with Interior Cleaner to protect the surface and make the next cleanup easier.

Which Product for the Job

• Active mildew or mold stains. Mildew Stain Remover. The dedicated formula, built for vinyl, upholstery, marine carpet, foam flooring and canvas.
• Keeping it from coming back. Interior Cleaner. Cleans and lays down UV protectant, so regular wipe-downs leave less for mildew to work with.
• Mildew in textured decking and marine carpet. Growth in non-skid and foam flooring sits down in the pattern where a wipe-down misses it. A boat deck cleaner foams into the texture and lifts it out.
• Wiping it all down. Interior Microfiber Towel. Plush enough for vinyl and canvas without dragging grit across the surface.

The rest of our boat cleaning supplies cover the wash-down that goes with it.

Mildew and Mold Questions

How do I stop mildew coming back every season?

Dry the interior before covering, keep some airflow under the cover, and wipe vinyl down with Interior Cleaner every few trips rather than waiting for black spotting to appear. Most repeat outbreaks trace back to a wet boat going under a sealed cover. Clean the cover itself too, since canvas stays damp longest and seeds everything below it.

Can I use it on canvas and boat covers?

Yes. Canvas, bimini tops and covers are all fair game, and they're usually where mildew starts. Spray, let it dwell, rinse or wipe. Spot test unfamiliar or heavily dyed canvas first.

What's the difference between Interior Cleaner and Mildew Stain Remover?

Interior Cleaner is your everyday wipe-down. It cleans and lays down UV protectant on vinyl and upholstery, but it isn't built to fight an active outbreak. Mildew Stain Remover is the dedicated formula for that job. It doesn't include UV protection, so follow up with Interior Cleaner once the stain is gone.

Will this get rid of really old, deep-set mold stains?

It's built for stubborn, baked-in mildew and mold including black mildew, and most active stains lift with one or two applications. Worth knowing: if mildew has worked its way deep into cushion foam or fabric fibers rather than sitting on the surface, a spray-on cleaner lifts the growth but may not fully restore fabric that's already discolored underneath. Catching it early is what keeps it from getting that far.

What surfaces is it safe on?

Vinyl, upholstery, cushions, plastic, marine carpet, foam flooring like GatorStep, and canvas or boat covers. As with any stain remover, spot test delicate or unfamiliar fabric first.

Do I need to scrub, or is spray-and-wipe enough?

Spray, wait one to two minutes, wipe. Light scrubbing helps on tougher, set-in spots.

Will it damage stitching or seams?

No. It's tough on mildew and safe on marine-grade stitching when used as directed.

Does it smell like bleach or chemicals?

No. It's a Mango Tango scent, so cleanup smells like the sandbar instead of a hazmat drill.