Garden Cushion Care: Can You Leave Them Outside, and How to Clean and Store Them

Updated October 2026 · By Sam K, Fabrica Kraft

Quick answer: Good-quality garden cushions made with outdoor fabric and quick-drying foam can handle the odd shower, but even the best ones last much longer if you bring them in or cover them when they're not in use, and store them over winter. To clean them, brush off dirt, then scrub with 1/4 cup of mild soap in about 4 litres of lukewarm water and rinse well. Before storing, make sure they're completely dry, then keep them in breathable bags somewhere dry and airy, raised off the floor.

British weather is hard on garden cushions. They get a few weeks of sunshine, a lot of drizzle, and then six months of damp. Many cushions are thrown away not because they've worn out, but because they were put away wet and came out of the shed in spring covered in mould. Here's how to keep yours looking good for years.

Can you leave garden cushions outside?

It depends what they're made of. Here's a simple guide:

Two things decide how a cushion copes with rain. The fabric: most outdoor fabrics, including most Sunbrella, are water-repellent rather than fully waterproof, so heavy rain can soak through the seams. And the foam: standard foam soaks up water like a sponge and can stay wet inside for days, which is when mould starts. Quick-drying open-cell foam lets water drain straight through.

Our guide to waterproof garden cushions explains the difference between water-repellent and waterproof in more detail.

How to clean garden cushions

1. Brush them dry first. Get rid of leaves, dust and bird mess with a soft brush. Wet dirt turns into mud.
2. Mix a gentle cleaner. 1/4 cup of mild washing-up liquid in about 4 litres (1 gallon) of lukewarm water. This is the ratio Sunbrella recommends for its fabrics.
3. Scrub gently with a soft brush or sponge, working from seam to seam.
4. Leave for a few minutes, then rinse thoroughly with a hose on a gentle setting until no soap is left.
5. Stand them on their edge to dry, somewhere breezy.

Removable Sunbrella covers can go in the washing machine on a cold, delicate cycle and should be air dried. For other fabrics, follow the care label. For Sunbrella specifically, see how to clean Sunbrella cushions.

Don't use a pressure washer. It forces water deep into the foam and damages stitching.

How to get green marks off garden cushions

That green tinge is usually algae, which grows on damp fabric in shady gardens. It's very common in the UK.

• On Sunbrella and other solution-dyed acrylics: Sunbrella recommends 1 cup of bleach and 1/4 cup of mild soap in about 4 litres of water. Spray the whole panel, leave for 15 minutes, scrub gently and rinse thoroughly. Keep bleach away from plants, lawns and ponds.
• On other fabrics: use white vinegar and water, mixed half and half. Spray, leave for 30 minutes, scrub and rinse. Bleach will fade most non-acrylic fabrics.

How to remove mould and mildew

Black or grey spots are mould or mildew. Treat them the same way as green marks, above. Then check the foam: if the cushion still smells musty once the cover is clean and dry, the mould is inside the foam. At that point, replacing the foam is the only lasting fix. See replace the foam or the whole cushion.

Drying: the step that decides everything

The US Environmental Protection Agency notes that wet items dried within 24 to 48 hours usually won't grow mould. In a British autumn, that can be tricky, so:

• Press out as much water as you can with a towel.
• Stand cushions on their narrow edge so water drains out.
• Bring them inside to finish drying near (not on) a radiator, or in a room with a dehumidifier.
• Press the centre with your palm. If it feels cool, it's still damp inside.

How to store garden cushions over winter

1. Clean them first. Dirt, pollen and sun cream left on fabric feed mould over winter.
2. Dry them completely. Never store garden cushions damp. This is the number one cause of spring mould.
3. Use breathable storage. Fabric storage bags, old cotton sheets or a breathable cushion bag let moisture escape. Sealed plastic bags trap any leftover damp.
4. Choose a dry, airy spot. A spare room, under a bed or a dry loft is ideal. Sheds and garages are often damp in winter, so if you use one, keep cushions off the floor on a shelf.
5. Keep them flat or on their edge, without heavy items stacked on top, so the foam doesn't get crushed.
6. Check them once a month. If you notice a musty smell, bring them inside and air them.

Garden storage boxes are handy during the summer, for quick overnight storage. Over winter, many boxes get damp inside, so add moisture absorbers or move cushions indoors.

Getting them ready for spring

• Air them outside on a dry, breezy day.
• Brush off any dust and spot clean.
• Re-apply a fabric protector spray if water no longer beads on the surface. Sunbrella suggests doing this after repeated deep cleans or after a few years of use.

When it's time to replace

Replace them if you see mould that keeps coming back, flat or crumbly foam, or fabric that tears when you pinch it. You often don't need a whole new cushion:

• Foam fine, fabric faded: order replacement outdoor cushion covers made to your old cushion's size.
• Fabric fine, foam soggy: replace just the foam with quick-drying Dry Fast foam.
• Both worn out: our replacement garden furniture cushions are made to fit the frame you already have, including rattan sets. See our replacement rattan cushions guide.

Every cushion is made to measure in outdoor fabrics such as Sunbrella, with free UK delivery and import duty and VAT already paid.

Frequently asked questions

Can garden cushions get wet?

Outdoor-fabric cushions can handle a shower, but dry them quickly. Standard foam holds water and can grow mould if it stays wet.

Can I leave garden cushions out over winter?

It's not recommended, even for good outdoor cushions. Clean, dry and store them indoors to make them last much longer.

Can you put garden cushion covers in the washing machine?

Many can. Sunbrella covers can be washed cold on a delicate cycle and air dried. Check the label for other fabrics.

Can you vacuum pack garden cushions?

Only if they're completely dry and clean, and not for long periods. Vacuum packing can crush some foams, and any trapped moisture will cause mould.

How do I stop garden cushions going mouldy?

Keep them clean, dry them quickly after rain, cover or bring them in when not in use, and store them fully dry in breathable bags.

Sources

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