decking-cleaner

5 Best Decking Cleaners for Mould, Algae & Dirt (2021 Review)

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In this guide we’ll take a look at the best decking cleaners for the UK market.
I’ve compared cleaning ability, treatment times, solution safety and cost
to give you my top recommendations.

What is the Best Decking Cleaner?

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Comparing The Best Decking Cleaners

Use the dropdown to sort the table by the feature that's most important to you.

  • Best For
  • Size
  • Max. Treatment Area
  • Cleaner to Water Ratio
  • Time to Visible Results
  • Application Method
  • Duration of Results
  • Rinsing Required
  • Free from acid & bleach?
  • Cost
  • Our score
  •  
    • Best decking cleaner overall
    • Size5 L
    • Max. Treatment Area200 m²
    • Cleaner to Water Ratio1:4
    • Time to Visible Results4 days
    • Application MethodSprayer or watering can
    • Duration of Results6 months
    • Rinsing RequiredNo
    • Free from acid & bleach?Yes
    • 4.55
    • CHECK PRICE →
    • Best value for money
    • Size5 L
    • Max. Treatment Area200 m²
    • Cleaner to Water Ratio1:4
    • Time to Visible Results2-3 days
    • Application MethodSprayer or watering can
    • Duration of Results6 months
    • Rinsing RequiredNo
    • Free from acid & bleach?Yes
    • 4.525
    • CHECK PRICE →
    • Best cleaner for large decking
    • Size5 L
    • Max. Treatment Area240 m²
    • Cleaner to Water Ratio1:5
    • Time to Visible Results2-3 days
    • Application MethodSprayer or watering can
    • Duration of Results6 months
    • Rinsing RequiredNo
    • Free from acid & bleach?Yes
    • 4.55
    • CHECK PRICE →
    • Best for fast results
    • Size5 L
    • Max. Treatment Area20-24 m²
    • Cleaner to Water RatioN/A
    • Time to Visible Results15-20 mins
    • Application MethodPour straight on the deck
    • Duration of ResultsNot listed
    • Rinsing RequiredYes
    • Free from acid & bleach?No
    • 4.45
    • CHECK PRICE →
    • Best eco-friendly decking cleaner
    • Size5 L
    • Max. Treatment Area200 m²
    • Cleaner to Water Ratio1:4
    • Time to Visible Results2-3 days
    • Application MethodSprayer or watering can
    • Duration of ResultsFew months
    • Rinsing RequiredNo
    • Free from acid & bleach?Yes
    • 4.375
    • CHECK PRICE →

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In-Depth Reviews of Our Recommended Decking Cleaners

Pro-Kleen 5 Litre Decking CleanerPro-Kleen 5 Litre Decking Cleaner

Best decking cleaner overall

Effectiveness
Speed of Results
Longevity
Value for Money
Overall
4.55
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Pro-Kleen 5 Litre Decking Cleaner Review

Specifications

  • Size: 5 L
  • Max. Treatment Area: 200 m²
  • Cleaner to Water Ratio: 1:4
  • Time to Visible Results: 4 days
  • Application Method: Sprayer or watering can
  • Duration of Results: 6 months
  • Rinsing Required: No
  • Free from acid & bleach?: Yes

You might be dreading your annual decking clean because it’s been such a mammoth task in the past. It can be laborious, as there’s often a lot of scrubbing and rinsing involved if you haven’t got the right products.

If you want to save as much time and effort as possible, you might like the Pro-Kleen 5 Litre Decking Cleaner. It’s one of the simplest products you could use, as it requires no rinsing or scrubbing!

You simply dilute 1 part cleaner to 4 parts water and apply it with a garden sprayer or watering can. Then, you can sit down with a cuppa whilst the solution gets to work!

Within a few days, any moss or algae should be dead, which you can then sweep away when it’s sufficiently loosened. Your deck should remain clean and slip-free for the next few months.

As well as working on moss and algae, this product can also reduce some species of weeds.

This decking cleaner can be used on any wooden surface including fences and sheds, as well as hard surfaces such as patios, driveways and walls. It won’t damage the paint on decking or fences. It can also clean uPVC windows, conservatories, boats and caravans.

Although diluting the product is recommended, this cleaner is highly effective on stubborn mould and algae when it’s used neat.

However, if you have particularly grimy decking, you might have to use a jet washer to get it perfect, as this cleaner is more effective at removing moss and algae than clearing dirt.

One pack of this product will produce 25L when diluted, providing plenty of cleaning product to get lots of your outdoor surfaces algae-free.

This product is non-acidic, bleach-free and biodegradable. Nevertheless, it’s recommended to keep pets and children away from the area until it’s dry.

Make sure you apply this product when dry weather is forecasted, as rainfall can dilute it further or wash it away, reducing its effectiveness.

Do take care with this product as it can cause burns and eye damage if used haphazardly. This is the same with all these kinds of products, so it shouldn’t be a reason to avoid this one.

This product’s large bottle might be cumbersome to handle, so it should be handled with care to avoid spillages.

Pros

  • Very easy to use, simply mix in watering can then drizzle across the decking
  • Gets to work quickly - customers report seeing results within just 4 days
  • Won’t damage painted decking or fence panels
  • Even more effective when used neat for very severe mould and algae

Cons

  • For very grimy decking, you may still need to use a jet washer
  • Although easy to use, it needs to be applied over a few dry days
  • More effective at removing moss and algae than it is at removing dirt
  • Care must be taken as this product can cause burns and eye damage
BUY HERE →

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Ultima-Plus XP Decking Cleaner 5 LitresUltima-Plus XP Decking Cleaner 5 Litres

Best value for money

Effectiveness
Speed of Results
Longevity
Value for Money
Overall
4.525
CHECK PRICE →

Ultima-Plus XP Decking Cleaner 5 Litres Review

Specifications

  • Size: 5 L
  • Max. Treatment Area: 200 m²
  • Cleaner to Water Ratio: 1:4
  • Time to Visible Results: 2-3 days
  • Application Method: Sprayer or watering can
  • Duration of Results: 6 months
  • Rinsing Required: No
  • Free from acid & bleach?: Yes

This next one’s the best decking cleaner for its value for money. It makes a minimum of 25L which can clean 200m² – ideal if you have a vast amount of decking or fencing to clean.

It’s the Ultima-Plus XP Decking Cleaner. It’s a super-concentrated mould and algae remover, with a highly powerful, yet eco-friendly, formula.

To use, mix 1 part of the solution with 4 parts water and apply with a spray or watering can. For less problematic areas, you can dilute the product with up to 9 parts water.

You should see a huge reduction in mould, moss and algae within 2-3 days. At this point it should be dead, brown and loosened, so you can brush it away.

While this product is slightly more expensive than others on my list, it has such a high dilution rate that a little goes a long way. Plus, it prevents the regrowth of mould and algae for 6 months, which is a longer amount of time than what other products promise.

Even if you only have small infestations of algae, this product can be diluted into a mild solution, so you can keep on top of these smaller breakouts.

This cleaner is suitable for all wooden surfaces as well as patios, brick, drives, tarmac, terracotta pots, statues, stone and uPVC windows.

Containing no acid or bleach, this cleaner is not only non-caustic but it’s also biodegradable. Even so, it’s advised to keep children and pets away until the area is dry.

Like most decking cleaners, this one should be applied when there’s no rain forecasted for a few days.

Customers report varying levels of success, depending on the seriousness of their mould problem. If you have black spot, a notoriously stubborn strain of mould, you might be better off buying a specifically designed solution to tackle these problem areas.

Be careful during application to avoid spraying nearby plants. A big drawback of cleaning products like this is that they can be so powerful that they can harm plants in your garden if they’re accidentally sprayed.

Pros

  • Simple to apply using just a watering can
  • Within a few days, many customers notice their moss turning brown and dying
  • The results are long lasting for many people - often up to 6 months
  • Biodegradable so an eco-friendly choice

Cons

  • Although safe for children and pets, they must still be kept off the treated area until it has dried
  • Many customers find results are more impressive if they use a stronger mixture - which makes this product less cost effective
  • Needs to be applied over a few dry days
  • Effects can vary from decking to decking and not everyone gets the same level of results
  • Need to be careful not to accidentally spray on other plants
BUY HERE →

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Jarder 5 Litre Concentrate Decking CleanerJarder 5 Litre Concentrate Decking Cleaner

Best cleaner for large decking

Effectiveness
Speed of Results
Longevity
Value for Money
Overall
4.55
CHECK PRICE →

Jarder 5 Litre Concentrate Decking Cleaner Review

Specifications

  • Size: 5 L
  • Max. Treatment Area: 240 m²
  • Cleaner to Water Ratio: 1:5
  • Time to Visible Results: 2-3 days
  • Application Method: Sprayer or watering can
  • Duration of Results: 6 months
  • Rinsing Required: No
  • Free from acid & bleach?: Yes

If every surface in your garden seems to be plagued by moss, lichen, algae and general grime, you might benefit from a multi-purpose product that can clean a variety of outdoor materials.

This Jarder 5 Litre Concentrate Decking Cleaner is one such product! It can be used on a wide variety of surfaces including decking, fences, stonework, gravel, driveways, roofs, greenhouses, garden furniture, terracotta and uPVC.

One pack makes a minimum of 30L of solution – enough to clean 240m². These numbers indicate great value for money, so this is probably the second best decking cleaner for value on my list.

It can be applied neat or diluted to different strengths, depending on the severity of the algae growth on your garden materials.

To use, simply dilute and spray on using a watering can. Leave it to get to work and within a few days, you’ll be able to sweep or brush away any dead moss.

For best results, you might have to use a jet washer alongside this product or use a stronger mixture. Furthermore, dry weather will ensure the best results as rain can wash the product away.

This product provides a barrier to prevent regrowth for up to six months, keeping decks slip-free and clean. This is a competitive length of time compared to other products on the market.

Free from acid and bleach, this cleaner is non-caustic and biodegradable. Once dry, the treated area is safe for children and pets.

Like all decking cleaners, this must be used with care around surfaces you don’t intend to clean, as it could stain them if they’re not listed as suitable surfaces.

Additionally, this product has been known to stain sandstone, so maybe steer clear of this one if that’s what you intend to clean.

Pros

  • Simple to apply with either a garden sprayer or watering can
  • Within a few days, your decking can look visibly cleaner
  • Good value for money with 30L covering 240m²
  • Biodegradable and contains no bleach
  • Results are long lasting for many people - with moss and algae staying away for up to 6 months

Cons

  • Needs to be used with care as it can stain some surfaces
  • Best results seem to appear with the addition of a jet wash
  • Some customers find results are best if they use a stronger mixture - which makes this product less cost effective
  • Although safe for children and pets, they still need to be kept away from the treated area until it has dried
BUY HERE →

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Ronseal DC Decking Cleaner 5 LitreRonseal DC Decking Cleaner 5 Litre

Best for fast results

Effectiveness
Speed of Results
Longevity
Value for Money
Overall
4.45
CHECK PRICE →

Ronseal DC Decking Cleaner 5 Litre Review

Specifications

  • Size: 5 L
  • Max. Treatment Area: 20-24 m²
  • Cleaner to Water Ratio: N/A
  • Time to Visible Results: 15-20 mins
  • Application Method: Pour straight on the deck
  • Duration of Results: Not listed
  • Rinsing Required: Yes
  • Free from acid & bleach?: No

This next product is slightly different from the others on my list as it’s designed to be used before the application of treatments such as oils or wood preservers. It’s the Ronseal DC Decking Cleaner.

Its other key difference is that you don’t need to fiddle about with dilution, however, this does make it less cost-effective than other products if you’re wanting to clean a large area of decking. One pack cleans a deck of around 24m².

The Ronseal cleans algae, mildew, dirt and stains as well as opening the pores of the wood to allow decking treatments to penetrate it.

The product can be applied with a garden sprayer, watering can or broom. It then should be scrubbed and rinsed later. After these steps, you can apply your chosen wood treatment.

Customer results seem to vary, reporting that a lot of rinsing is required due to excess residue.

This cleaner takes a little more work than other spray-and-leave products, but it’s the best decking cleaner if you’re planning to use wood treatments afterwards. It’s designed to help the oil or stain on your decking last longer.

Unlike other decking cleaners, this one can be used on wet and dry surfaces, so you don’t need to wait for dry weather to begin cleaning. A pressure washer will give superior results, whilst other decking cleaners do not require this.

Be sure to avoid contact with your skin and eyes.

Pros

  • Very effective at cleaning decking - with dramatic results visible on some deckings
  • Will help decking oil or stain to last longer, providing greater value for money
  • Can be applied on both wet and dry surfaces, so there’s no need to wait for the perfect weather

Cons

  • Not without physical effort - needs to be applied, scrubbed and rinsed
  • Still requires the use of a pressure washer for best results, unlike others on the market
  • A lot of care must be taken to avoid contact with eyes and skin
  • Effects can vary from area to area and not everyone gets the same level of results
BUY HERE →

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Dirtbusters 5 Litre Patio Decking CleanerDirtbusters 5 Litre Patio Decking Cleaner

Best eco-friendly decking cleaner

Effectiveness
Speed of Results
Longevity
Value for Money
Overall
4.375
CHECK PRICE →

Dirtbusters 5 Litre Patio Decking Cleaner Review

Specifications

  • Size: 5 L
  • Max. Treatment Area: 200 m²
  • Cleaner to Water Ratio: 1:4
  • Time to Visible Results: 2-3 days
  • Application Method: Sprayer or watering can
  • Duration of Results: Few months
  • Rinsing Required: No
  • Free from acid & bleach?: Yes

It’s a valid concern if you’re eco-minded that strong chemicals aren’t great for the environment. Fortunately, they’re not all bad. This next one is free from acids and bleach, so it won’t harm nearby wildlife.

This Dirtbusters 5 Litre Patio Decking Cleaner is another spray-and-leave product that provides enough to clean up to 200m² of decking or fencing. It can also be used on patios, paths, sheds, drives, garden furniture and uPVC.

Simply dilute 1 part solution with 4 parts water and apply with a hand pressure sprayer or watering can. Make sure to use the product when there’s no rain forecast as this can wash away the product.

This cleaner works quickly to kill algae in a few days and thick moss in about a week. It will also reduce regrowth for several months after application.

As with all cleaning products, be careful to avoid contact with skin and eyes, perhaps with the use of protective clothing and glasses. It contains no acids or bleach, but still make sure pets and children are kept away until the area is dry.

Results do seem to vary, indicating that the product may not be so effective on the black spot strain of mould, or oily stains.

Pros

  • Doesn’t contain bleach or acid, so won’t destroy painted decking nor harm wildlife
  • Safe to use on a range of outdoor surfaces including decking, fences, sheds, paths and garden furniture
  • Helps to control regrowth of moss and algae
  • Very simple to apply with just a watering can

Cons

  • Results can vary between deckings, with some users seeing dramatic results and others finding it not quite so effective
  • A lot of care must be taken to avoid contact with eyes and skin
  • Needs to be used during a few dry days
  • May not remove black spot or oily stains
BUY HERE →

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Things to Know Before Buying Decking Cleaner

As the weather warms up, we Brits are outside as much as possible and are reminded of all the different garden tasks that we’ve got to catch up on. One of them we often dread is cleaning the decking.

A decking cleaner has a huge range of uses; it’s a favourite purchase for sprucing up the garden without spending a fortune on a pressure washer, and it’s an effective way to kill and stop the spread of mould, algae and lichen.

If you’re considering purchasing decking cleaner but aren’t sure where to start, the following advice will get you up to speed:

Decking Cleaner Vs. Pressure Washer

While pressure/jet washers are popular options for deep cleans, they are much more expensive than a simple bottle of deck cleaner. Plus, if used too often, pressure washers can damage surfaces by dislodging grouting and getting under porous materials.

Another problem with using a pressure washer is that if you use one to clean a surface that has a covering of algae, moss or mould, the jet of water can spread the spores of these to other parts of the decking. Initially, the decking will look much cleaner, but you may quickly notice a wider spread of algae, moss or mould close by.

If you do want to use a pressure washer, you should consider using decking cleaner first to kill off the spores. This way they won’t spread around when you use the jet.

Decking cleaners are a much less abrasive option that won’t cause damage to your deck. What’s more, they offer long-lasting protection against algae and moss – these products stop this type of organic matter from growing back for several months.

In most cases, a decking cleaner is much less labour intensive than using a pressure washer, you simply spray or spread the diluted solution, wait for it to dry, and sweep away the dead moss, algae or lichen. You generally don’t need to rinse these products although there are some which require it. Be sure to read the manufacturer’s instructions carefully to see how to use the specific cleaner that you buy.

Look for a Safe Decking Cleaner

Decking cleaners can contain a range of chemicals, some harmful and some not.

Several of the cleaners in the reviews on this page promote the fact that they contain no acid or bleach, making them safe for children and pets once dry. If you have pets or kids who love to play outside, I highly recommend looking for one of these decking cleaners. They are also better for the environment.

Of course, the highest strength decking cleaners may contain some harmful chemicals, and it is these that make them so powerful and effective. As always, check the manufacturer’s instructions and be aware of exactly what chemicals you’re putting on your decking.

If you opt for one of these higher-strength cleaners, make sure you’re wearing all the necessary safety attire, such as goggles and gloves if acid or bleach are involved.

Ease of Use and Versatility

A deck cleaning solution is generally very easy to use. The dilution rate may vary between brands, so this is something to check with each different product. This is especially important to do if you’re used to using a particular one.

Pay attention to the coverage area of each bottle once diluted. Some smaller bottles may be better value for money if the product is more concentrated.

Take a look at which surfaces the deck cleaner can be used on. Most are safe to use on all wood and hard surfaces, but this is not always the case. It’s certainly something you’d want to double-check before applying the product, instead of learning the hard way!

Some decking cleaners are formulated to remove mould and black spots. These are generally applied neat to these areas. However, not all cleaners are suitable for this purpose, so check beforehand. It can save you money if you buy a decking cleaner that can also combat mould and black spots as you won’t have to buy two products.

If you’re looking to save time, look for a decking cleaner that doesn’t need rinsing after application. All you need to do is wait for the solution to dry. If you’re after hassle-free patio cleaning, this would be the best option for you.

Cleaners with Long-Lasting Results

Most decking cleaners not only get your decking gleaming, but they can also help keep mould and algae at bay for a few months after the first application.

Some decking cleaners reactivate when it rains, so there’s no need to reapply them frequently. The best decking cleaner can inhibit the growth of mould and algae for up to 12 months. Quite the result for such a quick job!

If you are having issues with a specific type of mould, look for a decking cleaner with a specially targeted formula.

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Decking Cleaner FAQs

Why should I use a decking cleaner? Can’t I just jet wash my deck and patio?

Jet washing can damage surfaces and be a labour-intensive and messy job. The advantage of using a decking cleaner is that it does the job without causing any damage. Plus, it will keep the surfaces clear of algae and moss for months after use.

Another reason why jet washing isn’t the best tactic for a moss/algae-covered deck or patio is that the powerful spray will disrupt the algae spores and spread them further and wider. This could mean that you end up with even more algae on nearby surfaces.

When should I apply decking cleaner?

It is best to apply decking cleaner on a dry, still day, ideally when no rain is forecast for the next few days. This will allow the product to get to work without getting washed away.

What safety precautions should I take when using decking cleaners?

You should ensure that children and pets are out of the way when applying these products. Decking cleaners can irritate the skin and damage the eyes so wear gloves when handling these products. You should also wear protective eyewear, especially if you are spraying the cleaner. Bear in mind that many cleaning products can be harmful to aquatic life so do not use them around ponds or watercourses.

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