Step 1.
The lazy way
If you’ve got plastic or hard wood lawn furniture and you’re in a hurry, a quick blast from a pressure washer could be all you need. This method might not get the best results, but it’s a quick fix for furniture that can take it – it’s not suitable for soft woods or painted surfaces.
Weigh down lightweight furniture first so that it won’t get blown away by the water pressure. Now connect your machine up to water and power, ideally using an RCD-protected plug socket, and a non-return valve to prevent water backflow. Keeping away from children and pets, follow the manufacturer instructions to prime your machine with water, and remember to wear eye and ear protection.
Use your wide-area nozzle or setting to blast off mould, moss and dirt, keeping away from any hinges or seals to avoid damage. Use a low power setting or stand at a decent distance, and be careful to avoid heavily weathered or softened areas of wood, which may not withstand the water pressure. If you’ve got a soft brush attachment, use that to get an effective but more gentle clean.
Step 2.
Cleaning plastic garden furniture
If you haven’t got a pressure washer, or using one didn’t clean your plastic furniture well, you’ll need to get a bit more hands on. A gentle scrub with warm soapy water is often enough to remove accumulated grime. You might need to be more vigorous to remove stubborn stains, but use a soft brush to avoid scratching the finish, particularly in highly visible areas like a table top.
Some stains don’t respond brilliantly to detergent. You can remove green algae by soaking in white vinegar, then gently scrubbing the surface clean, but be sure to apply it evenly to avoid a patchy result. If all else fails, plastic furniture will usually tolerate a bleach solution, but wear gloves and eye protection, and test an inconspicuous area first. Also, be sure to thoroughly rinse the furniture before anyone sits on it again.
Step 3.
Cleaning wooden garden furniture
Pressure washing isn’t usually suitable for soft or painted wooden garden furniture, although it may be an option if you have a soft brush attachment. It can be an option for oak and other hardwoods, but you should stick to wide-area nozzle patterns and comparatively low pressure. Otherwise, it’s best to gently scrub dirty wood with warm or soapy water. Rub unpainted surfaces along the direction of the grain to remove entrenched dirt, then rinse them clean. Use a towel to dry off excess water, then air the furniture to get it fully dry.
Use care on painted wooden surfaces, as paint and varnish can flake or peel off with pressure washing or vigorous scrubbing. If that’s already happening through age and exposure, you may need to strip and re-coat the furniture to extend its life. Harsher chemicals like vinegar and bleach can spoil the appearance of wood, so it’s best to only use them as a last attempt when the alternative is painting over or scrapping the furniture.
Step 4.
Cleaning metal garden furniture
It’s usually safe to clean galvanized and bare metal furniture frames with a pressure washer’s rotating or fan nozzle, but you should keep away from seals, hinges and latches. Medium or high-power cleaning should remove any dirt, moss or other stains, but you may need detergent – and possibly warm, soapy water with a brush – for any oil-based staining such as tar.
You can use a pressure washer on painted metal furniture, too, but you’ll need to be more careful to avoid stripping paint. Avoid flaking or bubbling paint, which won’t withstand a water jet. Use a fan nozzle or setting, and spray with a low power or from a greater distance.
Step 5.
Cleaning fabrics
Even treated fabrics lose their weatherproofing over time, while anything enduring a British winter is likely to collect bird droppings, and even mould and lichen. It’s best to clean and dry parasols and cushions before dirt has a chance to settle in, but dirty materials can often be revived with warm soapy water and gentle wiping or sponging. Rinse clean afterwards, and leave to dry naturally. Check cushions for removable covers – if they’re washable, a quick trip through the machine should be very effective.
It’s harder to restore mouldy fabrics, which may be damaged as well as discoloured, but if all else fails, a mould remover spray – or a 10:1 dilution of bleach – can be effective. Wear goggles and gloves for protection, and test first on an inconspicuous area, remembering that bleach-based solutions will almost certainly discolour natural fabrics. Leave a few minutes for the solution to work before agitating gently and thoroughly rinsing the fabric clean.
Step 6.
Aftercare
To protect your garden furniture from getting dirty again, store it inside if you can. Failing that, at least use a cover. Otherwise, bring any cushions and parasols indoors when not in use, then tip chairs forward to encourage rain to run off. You can protect plastic from the elements by applying a clear lacquer to clean, dry furniture. Similarly, you can stain, varnish or paint wood, and paint metal items – but make sure you choose appropriate outdoor products, and follow the directions to prepare the surface properly.
It’s a good idea to grease or oil any hinges, latches or other moving parts after washing furniture. This can prevent rust, and keep parasols and recliners working smoothly. You can prolong the life of painted wooden and metal furniture by properly stripping, treating and repainting any rust or rot. In all cases, be sure any treatment is fully dry before use, especially on chairs – nobody wants linseed oil on their best linen trousers.
