How To Clean Mildew Off Of Patio Cushions

How to Clean Mildew off of Patio Cushions

Once your patio space has been perfectly created, spending time with friends, family and guests while enjoying the outdoors makes for summer living. You may have a table and a few chairs on your patio or a large and luxurious sofa set, your patio is your piece of heaven.

QILLOWAY  Patio Wicker Seat Cushions

There’s nothing worse than a musty smell and unsightly stains on your outdoor furniture. Mildew is an unwanted guest that can ruin your patio furniture – here we’ll show how to clean mildew off of patio cushions.

What is Mildew?

Mildew is more common on patio furniture than you think. In fact, it is a common household problem too and one that is most prevalent in our bathrooms where conditions are regularly hot and damp for mildew to take root. Mildew (also called mould depending on where it is found) is the scourge of outdoor fabrics: mildew can set in very quickly and can actually make people very ill if they inhale large quantities of mildew spores. It appears mostly on patio furniture after a short period of rainy weather, on the underside of patio cushions where it is damp, dark, and warm.

Mildew of Patio Cushions
Image Credits: LoveofFamilyandHome

As the mildew are living organisms, they grow and spread quickly. They eat fabrics’ fibers, causing damage and can weaken the fabric’s construction. It is best to get rid of mildew as soon as you see it appear on your patio cushions and before it has a chance to spread to other areas of your patio furniture. Cleaning mildew off of patio cushions isn’t a tricky or difficult task, but it does require some time and elbow grease. Don’t be dismayed if you spot mildew on your cushions: mildew can be removed and you can prevent any anyone getting sick from inhaling the mildew spores.

Types of Patio Cushion Materials

To know how best to remove mildew and clean your patio cushions, you must first know what fabric the cushions are made from. Look for the care instruction tag (usually found near the zipper or buttons) to find out, or if yours has no tag it is easy enough to discern between the different fabrics. All patio cushions are made from synthetic materials. They manage to feel soft yet are hardy to withstand the harsh effects of the sun’s rays and rainy days too, as well as being exposed to food sauces, sunscreens, drinks, and other debris, while still looking new. That’s due to the water- and weather-resistant coatings sprayed on them by the manufacturers, but repellents do eventually break down and that’s when mildew, permanent stains, and fading become problems.

QILLOWAY  Patio Wicker Seat Cushions

There are 2 main types of materials used for patio cushions: acrylic and polyester fabrics. There are differences between these 2 that determine how you will be able to approach cleaning and caring for them.

Acrylic is soft to the touch, is water- and weather-resistant, and come in a wide variety of patterns and colors. These can sometimes be washed in your home’s washing machines (by following the care instructions) and can also be treated with bleaches (once more, this must be following the care instructions and depends on the colors and dyes of the acrylic fabric).

Polyester fabric is a strong material in terms of construction and polyester patio cushions are very affordable. The drawbacks are that this type of fabric does begin to fade sooner than acrylic fabric patio cushions. Polyester patio cushions can’t be treated with bleaches as the cleaning agents are too strong and will damage the fabric’s fibers. These types of patio cushions can, however, be washed in washing machines and dry off quickly in the sun.

Now that you know more about the types of fabrics and have identified what materials your patio cushions are made from, we can now proceed to clean mildew off of your patio cushions.

Items Needed for this Task

1. Bucket
2. Spray bottle
3. White Vinegar
4. Bleach
5. Lysol
6. Laundry Detergent
7. Sponge
8. Soft-bristled brush

How to Clean Mildew off of Patio Cushions

Clean Mildew off of Patio Cushions

As we’ve mentioned, there are different cleaning methods for the different types of patio cushion materials. We’ll walk you through how to best clean mildew off the polyester fabric and acrylic fabric cushions.

Step #1

For both material types, always test clean a hidden area of the cushion before you soak the visible areas affected by the mildew so you can make sure that your cleaning solution doesn’t damage the fabric.

Step #2

Using your soft-bristle brush, give your patio cushions a thorough scrubbing to remove dirt and debris to get a better idea of how many areas are affected by mildew and to what extent. This is a process best handled by covering your mouth and nose with a mask to avoid inhaling any mildew spores that might be released by your scrubbing actions.

Step #3

To clean acrylic or polyester cushions, mix your cleaning solution into a gallon of warm water.
• Polyester: The most harmless solution to attempt first is to mix ½ cup of white vinegar into your bucket of hot water. Dip your sponge into this solution and wipe it over the affected areas.
• Acrylic: Mix 1 cup of bleach (remember to first apply it to a test area to see whether it damages the fabric or not) and 2 cups of laundry detergent into the bucket of water. Use a spray bottle to fill up with some of your mixture to spray onto the affected mildew areas of your cushions.

Step #4

• Polyester: The next step is to use your soft-bristled brush to give the cushions a deeper scrub before allowing the white vinegar’s active ingredients to get to work on killing the mildew.
• Acrylic: Let that bleach sit on the cushion for 30 minutes before thoroughly rinsing the bleach off and letting the cushion dry in the sun. If your acrylic cushions don’t handle bleach well from your test clean, you should use the same cleaning solution as outlined for polyester cushions as it will work well but will require repeated cycles to completely remove mildew.

Step #5

Polyester: Allow the cushions to sit in the sun for 3 or 4 hours after which you can rinse off the white vinegar with clean water. If you see other mildew spots, repeat the process until they’re all cleaned off. For stains and marks that are stubborn, mix ½ cup of your laundry detergent into a gallon of warm water, and then use your sponge to rub that solution over the mildew marks. Again, wash it off with clean water and allow to air dry in the sun.
• Acrylic: Rinse off the bleach solution from your patio cushions with your sponge and clean water. You could also dunk your cushions into the bucket to ensure none of the bleach remains on the cushions and then sit them in the sun to completely dry off.

Preventative Measures

Once you’ve removed the mildew you can maintain its cleanliness with regular, quick cleans. Prevention is also better than cure: if you’re going away on holiday or you know rainy weather is on its way, store your patio cushions inside to avoid them getting wet and then allowing mildew to grow.


While mildew is a cause for concern as it can lead to health complications for people and pets, it is actually quite easy to clean mildew off of patio cushions. With simple home ingredients and some elbow grease, your patio cushions will be mildew-free and will return your patio to being your slice of outdoor paradise.