How to Clean Outdoor Cushions (and Get Rid of Mold and Mildew for Good)

Updated October 2026 · By Sam K, Fabrica Kraft

Every spring we get the same photo in our inbox. A patio cushion that looked fine in October comes out of storage in April covered in little grey-green dots. Most of the time, that cushion can be saved. But the cleaner you pick matters a lot. The wrong one can ruin the fabric faster than a whole season of rain.

This guide explains, in plain steps, how to clean outdoor cushions, how to get rid of mold and mildew, and how to tell when a cushion is past saving.

Quick answer: how do you clean outdoor cushions?

Brush off loose dirt first. Mix 1/4 cup of mild soap into 1 gallon of lukewarm water, scrub with a soft brush, and rinse until no soap is left. Then stand the cushion on its edge to dry in a breezy spot. For mold or mildew on Sunbrella fabric, Sunbrella recommends 1 cup of bleach and 1/4 cup of mild soap per gallon of water, left on for 15 minutes and rinsed off completely.

Key facts at a glance

Step 1: Check what your cushion is made of

Most people skip this step, but it decides everything else. Look at the tag near the zipper, or find the original product listing. You need to know two things.

What fabric is it? Solution-dyed acrylic fabrics, such as Sunbrella, have their colour added while the fibre is being made, so the colour goes all the way through. That's why they can handle diluted bleach. Printed polyester and cotton canvas are coloured only on the surface. Bleach will leave pale patches on them that never come back.

Does the cover come off? If it has a zipper, you can wash the cover properly. If it's sewn shut, you'll clean the cushion as one piece, and you'll need to be careful with water.

No tag? Test any cleaner on the underside first and let it dry before you decide whether it's safe.

Step 2: Do the everyday clean

This handles normal dirt, pollen and the grey film that builds up over a summer.

1. Brush or vacuum it dry. If you add water first, the dirt turns to mud and sinks into the fabric.
2. Mix the solution. Use 1/4 cup of mild soap, like Dawn dish soap or Woolite, in 1 gallon of lukewarm water. Hot water can set some stains.
3. Scrub gently. Use a soft-bristle brush or sponge. Sunbrella suggests working from seam to seam, not in circles, so you don't leave a ring.
4. Let it sit. Give the soap a few minutes to loosen the dirt.
5. Rinse well. Use a garden hose on a gentle setting. Soap left behind attracts new dirt, so keep rinsing a bit longer than you think you need to.

Don't use a pressure washer. It pushes water deep into the foam, weakens the stitching and can damage the weave.

Step 3: How do you get rid of mold and mildew on outdoor cushions?

Mildew is a flat, powdery growth that sits on the surface. Mold is fuzzier and grows deeper. Both need the same three things: moisture, something to feed on (pollen, sunscreen, food crumbs) and still air. Take away any one of those and they stop spreading.

On Sunbrella and other solution-dyed acrylics:

1. Mix 1 cup of bleach and 1/4 cup of mild soap into 1 gallon of water.
2. Spray the whole panel, not just the spots. This stops you getting a clean patch with a dirty ring around it.
3. Leave it for 15 minutes.
4. Scrub lightly with a sponge or very soft brush.
5. Rinse until you can't smell any bleach.

Keep bleach away from plants, ponds, lawns and any fabric that isn't Sunbrella. Wear gloves and work outside.

On polyester, cotton or fabric you're unsure about: Use white vinegar mixed half and half with water, or an oxygen-based cleaner made for fabric. It works more slowly, but it won't strip the colour.

For the smell: Once the cushion is fully dry, sprinkle baking soda over it, leave it overnight, then vacuum it off.

Now do the sniff test. If the cover looks clean but the cushion still smells musty the next day, the mold is inside the foam. Cleaning the outside won't fix that.

For a deeper look at mold, including safety gear, which cleaners suit which fabrics, and how to tell surface mildew from mold inside the foam, read our guide to getting mold out of outdoor cushions.

Step 4: Dry it properly, or the mildew comes back

This is where most people go wrong. A cushion can feel dry on the outside and still be wet in the middle for days. The US Environmental Protection Agency says that if wet items are dried within 24 to 48 hours, mold usually won't grow. So speed matters.

• Press out as much water as you can with a towel.
• Stand the cushion on its narrow edge so water drains down and out.
• Put it somewhere with moving air. A covered cushion can sit in the sun for a few hours, but don't leave bare foam in strong direct sun for long, because UV breaks foam down.
• Turn it every couple of hours.
• Press the center with your palm before you put it back. If it feels cool or damp, give it more time.

The foam is usually the real problem. Standard polyurethane foam holds water like a kitchen sponge. Our Dry Fast foam has a very open structure, so water runs straight through it and out of the cushion. It dries in hours, not days. If you live somewhere humid or rainy, it's the best upgrade you can make.

Can you put outdoor cushion covers in the washing machine?

Sunbrella covers can go in the washing machine. Close the zippers, wash on a cold, delicate cycle with mild detergent, and air dry. For heavy mildew, Sunbrella says you can add 1 cup of bleach to the wash. Don't use a tumble dryer, and don't use a steamer or steam iron. For other fabrics, follow the care tag. If there's no tag, wash by hand.

Put the cover back on while it's still slightly damp. It eases back over the foam more easily and dries smooth.

When is a cushion not worth cleaning?

Be honest here. It's time to replace something if you see:

• Black spots that come back within a week or two of cleaning (the foam itself has mold)
• Foam that's flat, crumbly, or yellow and dusty
• Fabric that tears when you pinch it, which means sun damage that no cleaner can reverse
• Split seams or zippers that won't close

You often don't need to replace the whole cushion:

• Fabric fine, foam bad: replace just the foam from our custom-cut foam collection.
• Foam fine, fabric faded: order replacement outdoor cushion covers made to your old cushion's size.
• Both worn out: our Sunbrella replacement cushions are made to fit the frame you already own.

Still not sure? Our guide on replacing the covers or the whole cushion walks through the decision.

How to stop mold coming back

• Brush cushions off every week or two in summer.
• Wipe off sunscreen, food and bird droppings the same day. They feed mildew.
• After heavy rain, tip cushions onto their edge instead of leaving them flat.
• Store them clean and fully dry, in breathable bags, somewhere with airflow. Sealed plastic traps moisture.
• When you replace them, pick materials made for outdoors. Sunbrella outdoor cushions with Dry Fast foam are about as low-maintenance as outdoor seating gets.

FAQ

Can I use bleach on all outdoor cushions?

No. Diluted bleach is safe on solution-dyed acrylics like Sunbrella, but it will discolor most polyester, cotton and printed fabrics. Always test a hidden spot first.

Is Sunbrella fabric waterproof?

Most Sunbrella upholstery fabric is water-repellent, not waterproof. In heavy rain, water can get through seams and into the foam. Some ranges, including Sunbrella's marine collections, are waterproof.

How often should I clean outdoor cushions?

Give them a quick brush every couple of weeks during the season, and a full clean at the start and end of summer. Clean spills as soon as they happen.

Can I clean outdoor cushions with vinegar?

Yes. A 1:1 mix of white vinegar and water is a gentle option for mildew on fabrics that can't take bleach. Rinse well afterward.

Not sure if your cushion is worth saving? Email a photo to care@fabricakraft.com and we'll give you an honest answer.

Sources

• Sunbrella: How to clean Sunbrella upholstery
• US EPA: A Brief Guide to Mold, Moisture and Your Home