Outdoor cushions collect pollen, sunscreen, bird droppings and, if they stay damp, mildew. Most can be cleaned at home with mild soap and water, but the right method depends on the fabric and on what the maker allows, so start with the care label.

This guide covers routine cleaning, washing removable covers, dealing with mildew and drying cushions so the problem does not come back. For cushions with covers that makers say can go in the washer, see Best Outdoor Deep Seat Cushions and Best Outdoor Bench Cushions.

Start With the Care Label

Every cushion maker sets its own limits. Some say covers are machine washable on a cold, gentle cycle. Others ask for spot cleaning only, because washing can damage a water-repellent coating or shrink the cover so it no longer fits the foam.

If the label is gone, look up the listing or the maker's website before you use anything stronger than mild soap. When in doubt, treat the cushion as spot clean only.

Routine Cleaning

  • Brush off loose dirt and leaves with a soft brush before it gets wet and grinds in.
  • Mix a mild dish soap with lukewarm water.
  • Sponge the fabric gently, working from the outside of a stain toward the center.
  • Rinse well with clean water, because leftover soap attracts dirt.
  • Stand the cushion on its edge to drain and dry.

Avoid stiff brushes and pressure washers. They can fray fabric and force water deep into the foam.

Washing Removable Covers

If the maker allows machine washing, close the zippers, turn the cover inside out and use the cycle and temperature on the label. Many outdoor covers should not go in a hot dryer, and some should air dry only.

Put the cover back on while it is still slightly damp. It stretches more easily, and it will fit snugly as it dries. Never put a damp cover back on wet foam.

Removing Mildew

Mildew shows up as gray or black spots on fabric that stayed damp. It often grows on dirt and body oils on the surface, so cleaning matters as much as the mildew treatment.

Start with mild soap and water. If spots remain, check whether your fabric maker allows bleach. Some solution-dyed acrylic fabric makers, such as Sunbrella, publish a diluted bleach solution for mildew on their own fabric. Use their exact instructions and only on fabrics that permit it, because bleach can strip color from printed or yarn-dyed polyester.

Always try any cleaner on a hidden spot first, work outdoors, wear gloves, and never mix bleach with ammonia or other cleaners.

Drying Properly

Most mildew problems come from cushions that never fully dry. After cleaning or rain, stand cushions on edge in a sunny, breezy spot and turn them so every side gets air. Squeeze water out of foam gently instead of wringing it.

Do not store a cushion until both the cover and the foam are dry all the way through. A cushion that feels dry on the outside can still be wet in the middle.

Preventing Stains

  • Bring cushions in or store them in a bag or box when rain is forecast.
  • Wipe spills and bird droppings promptly.
  • Use towels over cushions when you sit in sunscreen.
  • Store cushions off the ground in a dry space over winter.

For storage options, see Best Outdoor Cushion Storage Bags and Best Deck Boxes.

FAQ

Can I put outdoor cushions in the washing machine?

Only the covers, and only if the maker allows it. Foam inserts should not go in a washer or dryer.

Can I use bleach on outdoor cushions?

Only if the fabric maker says so. Bleach can fade printed and yarn-dyed fabrics and weaken some coatings.

Why do my cushions keep getting mildew?

They are probably staying damp. Dry them fully after rain, keep them off the ground, and store them dry.

The Bottom Line

Clean outdoor cushions gently with mild soap and water, follow the care label for anything stronger, and dry them completely before storing. Most mildew problems are moisture problems, so drying and storage do more than any cleaner. For cushion options, see Best Outdoor Cushions.