Key Takeaways -

• Regular cleaning prevents dirt buildup, mould, and slippery surfaces.
• Use the right cleaning methods for wooden and composite decking.
• Protective treatments like stains and oils help extend the decking's lifespan.
• Sweeping and routine maintenance keep decking looking fresh year-round.

Garden decking can get dirty over time, but with the right steps, you can keep it clean and in great condition. Regular cleaning helps prevent stains, mould, and slippery surfaces, making your decking safer and longer-lasting.

This guide will show you eight simple steps to clean your garden decking easily. You’ll learn how to remove dirt, tackle stubborn stains, and protect your decking from damage.

Keep reading to find out how to make your decking look fresh and well-maintained all year round. No matter what type of decking you have, these easy cleaning tips will help you keep your outdoor space looking its best.

Why Cleaning Your Garden Decking Is Essential

Keeping your garden decking clean is important for both its appearance and durability. Over time, dirt, stains, and moisture can build up, leading to long-term damage. Regular maintenance helps prevent these issues, ensuring your decking stays safe, sturdy, and looking great all year round.

The Benefits of Regular Decking Maintenance

• Improves aesthetics and extends lifespan: A clean deck looks fresh and inviting. Removing dirt and grime helps prevent long-term wear, keeping the decking in good condition for years.
• Prevents slippery surfaces caused by moss and algae buildup: Moss, algae, and mildew can make decking dangerously slippery. Regular cleaning reduces this risk, making it safer to walk on.
• Enhances the overall safety of your outdoor space: A well-maintained deck reduces the chances of accidents, splinters, or rotting wood, ensuring a safe environment for your family and guests.

Common Problems With Dirty Decking

• Surface dirt and debris accumulation: Leaves, dust, and debris collect on decking, making it look unkempt and providing the perfect conditions for mould and moss to grow.
• Stubborn stains from food, drinks, or organic matter: Spilled food, drinks, or fallen leaves can leave tough stains that are difficult to remove if not cleaned quickly.
• Growth of mould, moss, and algae: Moist conditions encourage the growth of mould and algae, making the decking unsightly and dangerously slippery.
• Wood deterioration due to moisture and grime: When dirt and moisture are left untreated, they seep into the wood, causing it to rot, weaken, and shorten its lifespan.

Preparation Before Cleaning Your Decking

Choosing the Right Day for Cleaning

Pick a dry day with mild temperatures to allow your decking to dry properly after cleaning. Avoid cleaning during rainy or overly humid conditions, as excess moisture can make drying take longer and encourage mould growth.

A calm, sunny day is best, but try to avoid direct sunlight, as cleaning solutions can dry too quickly and leave streaks.

Clearing the Decking Area

Start by removing all furniture, plant pots, and decorations to give yourself full access to the decking surface. This prevents obstacles from getting in the way and makes cleaning more thorough. Use a soft-bristled brush or broom to sweep away leaves, dirt, and debris.

Check for any loose deck boards, cracks, or signs of rot, as these should be fixed before cleaning to prevent further damage.

Gathering Cleaning Supplies

Having the right tools and cleaning products makes the job easier. A broom, soft-bristled brush, bucket, and garden hose are essential. For cleaning solutions, you can use mild washing-up liquid or a specialist decking cleaner designed for wood or composite decking.

Protective gear like gloves and safety glasses is recommended, especially when using stronger cleaning products, to protect your skin and eyes.

Step-by-Step Guide to Cleaning Garden Decking

Step 1: Clear the Deck Area

Remove all furniture, plant pots, and decorations so you can clean the entire surface properly. Inspect the decking for damage, such as loose boards or cracks, and make any necessary repairs. Sweeping away leaves and debris prevents staining and moisture buildup, which can lead to mould or rot.

A completely clear deck makes cleaning easier and more effective.

Step 2: Sweep the Deck

Use a stiff-bristled broom to sweep away loose dirt and dust. Pay extra attention to corners and grooves where debris can collect. If particularly problematic dirt is stuck between the boards, use a putty knife or a small brush to dislodge it.

This step helps prevent grime from being pushed deeper into the wood when scrubbing later.

Step 3: Rinse the Deck

Use a garden hose to rinse the entire decking surface. If using a pressure washer, set it to the lowest pressure to avoid damaging the wood. Keep the nozzle a few feet away and spray in the direction of the wood grain to prevent splintering. Rinsing removes loose dirt and prepares the deck for cleaning.

Step 4: Apply Cleaning Solution

Mix warm water with washing-up liquid or use a specialised decking cleaner. Apply the solution evenly across the decking with a mop or sprayer. Let it sit for 5–10 minutes to break down grime and loosen tough stains. This allows for easier scrubbing and ensures a deep clean.

Step 5: Scrub the Surface

Use a stiff-bristled brush to scrub away stains, mildew, and algae. Focus on high-traffic areas and stubborn stains that need extra attention. For composite decking or delicate finishes, use a soft brush or sponge to avoid scratching the surface. Scrubbing thoroughly ensures a cleaner, safer deck.

Step 6: Rinse Again

Rinse the deck with clean water to remove all soap residue. Leftover cleaning solutions can cause streaks or interfere with protective treatments. Ensure all product is washed away to keep your decking looking fresh and ready for use.

Step 7: Treat for Mould (Optional)

If you notice mould or mildew, apply a specialist mould treatment product. This helps prevent future growth and keeps your decking looking clean for longer. Follow the product instructions carefully and allow the deck to dry fully before proceeding.

Step 8: Apply Protective Treatment (Optional)

Once the deck is completely dry, consider applying a protective stain, oil, or paint to help prevent future damage. Choose a dry day for application to ensure the best results. A protective treatment enhances the decking’s appearance and extends its lifespan.

Special Considerations for Different Decking Materials

How to Clean Wooden Decking

Wooden decking is more delicate than composite, so avoiding excessive water exposure is key. Too much moisture can lead to wood rot and warping. Use a specialist wood cleaner or a natural reviver to restore its original colour and remove dirt (1).

Once clean and dry, apply a protective stain or oil to seal the wood, preventing moisture damage and extending its lifespan.

How to Clean Composite Decking

Composite decking is easier to maintain but still needs regular cleaning. A mild soap and water solution is enough to remove dirt without damaging the surface. Scrub gently using a soft-bristled brush to avoid scratching. Avoid abrasive tools or harsh chemicals, as these can weaken the material.

Regular cleaning helps prevent buildup and keeps composite decking looking like new.

Frequently Asked Questions

Can I Use a Steam Cleaner on My Decking?

It’s not recommended to use a steam cleaner on decking, as the high heat and moisture can damage the surface. For wooden decking, steam can weaken the fibres and cause warping over time. Composite decking may also suffer from discolouration or surface damage.

Instead, use a mild cleaning solution with warm water and a soft-bristle brush for safe and effective cleaning.

Is Decking Stripper Safe to Use on Traditional Wood Decking?

Yes, decking stripper is safe to use on traditional wood decking when applied correctly. It helps remove old stains, sealers, and dirt, making it easier to restore the wood whilst cleaning up deep-set grime.

Always apply a thick layer of decking stripper and allow it to sit for the recommended time before scrubbing or rinsing. Be sure to follow the manufacturer’s instructions and test on a small area first.

How Do I Tackle Algae on Older Decking?

Algae can make older decking dangerously slippery, but it can be removed with the right approach. Use a specialist algae remover or a solution of water and vinegar to break down the growth. Scrub the surface gently and rinse thoroughly, especially if you plan to treat it with a protective coating.

If replacing damaged boards, ensure they match the new wood to maintain a uniform appearance.

How Do I Remove Grease or Oil Stains from My Decking?

To remove grease or oil stains, start by sprinkling baking soda or sawdust over the affected area to absorb excess residue. Let it sit for 10–15 minutes before scrubbing it with warm, soapy water and a soft-bristled brush. For tougher stains, a specialised decking degreaser can help break down the oil.

Rinse the area thoroughly to prevent any cleaning residue from affecting the wood.

What’s the Best Way to Remove Rust Stains from Decking?

Rust stains on decking can be treated with a mixture of lemon juice and baking soda. Apply the solution to the stain, let it sit for a few minutes, then scrub gently with a soft brush. If the stain is stubborn, use a mild rust remover that is safe for decking materials.

Rinse thoroughly to prevent residue buildup, and repeat the process if necessary.

Conclusion

Keeping your garden decking clean and well-maintained is essential for its longevity and safety. By following the right steps, you can clean decking effectively, remove stains, and prevent issues like mould and algae buildup.

Regular maintenance will keep your outdoor space looking fresh and inviting all year round. With the right cleaning methods and protective treatments, your decking will stay in excellent condition for years to come.

Sources -

1. https://www.cladcodecking.co.uk/blog/post/how-to-clean-wood-decking