How to stop green mould and algae from growing on your patio?

If you wonder how to keep the patio from turning green and are looking for an answer, then this is the most important thing you will read today.

Here’s why: In this guide, we’ve talked about how to stop algae from growing, how to clean it and how to waterproof your deck and patio.

Let’s start.

clean block paving patio before and after

Why does the floor go green?

Moss, algae, moulds, and weeds grow because of excess moisture in the patio. When there’s water between your paving bricks, it becomes the perfect condition for moss and algae to make their spores. Improper drainage in the patio is the prime reason for your green floor.

The second reason you have algae in the yard is improper sunlight. Algae and moulds often grow in shady areas where the sunlight is blocked. Because sunlight evaporates all the moisture from the patio and makes it clean-dry.

Another reason is the presence of bacteria and the air. Our patios are filled with bacteria which are favourable for the growth of algae and moss. That’s the reason why a single spore of algae multiplies itself into a million spores within weeks.

So, if you live in humid areas or if you frequently use water for any purpose on your driveway/patio, and it does not have a proper drainage system, then you will face algae and mould problems in your yard. Also, if there is improper sunlight on your patio because of trees and sheds, you’re letting algae seize the patio.

how to clean green mould from paving block patio

How to remove green algae from stone?

Although algae does not harm the physical properties of the concrete, it surely makes it slippery, which can be hazardous to you and your family. That’s why it is imperative to remove it from time to time.

There are several methods to remove algae from your yard. Some require professional tools and chemicals and others require things from your kitchen. We will check them out one by one. Starting with…

Power Washer:

The quickest way to remove algae, moss, moulds, or any other artificial stain from your patio. All you have to do is to turn on the pressure washer and point your nozzle towards the algae, and just start scraping it with the water pressure. It not only looks satisfying to watch but makes your patio look brand new.

Power Washing Patio And Protected Happy

However, you need to be careful with these machines. The power washer throws water at extremely high pressure and if you put too much of that at one place, it may scrap the concrete itself, or if you put too much water pressure on the joints, it may even disturb the sand base underneath the patio.

Make sure to read the manuals and use the correct angle to get the maximum out with a minimum loss.

Algae Removers:

Next method is to use chemical-based treatments. You can use annihilators to get rid of all the algae on your patio. Algae annihilators are solutions that if applied on a green patio quickly destroy all the weeds, moulds, and algae grown between the joints.

These chemicals leave a pungent smell after their use and are harmful to your eyes and skin. So, we advise you to use all the protective equipment required to use them.

In properla, we have in our catalogue: proPERLA Cleaner is a concentrate that cleans, disinfects and protects against green contamination growth on walls, roof, paving slabs and other exterior surfaces.


One of the most common and easily available materials used to treat green patios. Bleach when it comes in contact with any green plant, weed, or algae immediately burns it down.

It is not advised to use bleach on artificial block pavings as it may fade the colour and weakens the structure of the concrete.

House cleaners:

The last thing which is commonly used to remove Algae is household cleaners like washing liquid/powders or soaps. These products contain different chemical substances in them that weaken the algae spore and make it easier to clean.

After washing the yard with soap and water, quickly scrape or brush the algae. After scrapping it, remove every spore from the patio.

proPERLA® Paving Impregnator for a long-lasting protection of your paving stones.

Water based solution, designed with the latest nanotechnology. It can be used on all mineral surfaces, such as concrete slabs, paving stones, terraces and many more

properla paving impregnator

How to stop algae from growing on decking?

We have talked about how you can clean and prevent algae from block pavings but what about wooden decks? Let’s check how you can protect your wooden deck.

The algae grow on the wooden deck for the same reason; Moisture and lack of sunlight. If your deck remains wet for long periods, there’s a good chance that it will end up being green with algae. So, try to keep it warm for as long as possible.

Also, the debris on the deck prevents it from getting enough sunlight and the algae starts to build up beneath the debris. Make sure to clean the deck regularly.

You can also make the wooden deck waterproof by applying proPERLA wooden impregnator that seals the wooden deck and makes it up to 95% hydrophobic. It not only will make the deck algae-proof, but it will also make it safe from artificial stains.

proPERLA® Wood impregnator for a long lifespan of your wood surfaces.

It protects wooden surfaces such as hardwood terraces, beams or wooden boards against premature aging.

wood show 2

Ending note

If you’re not a DIY’er and need help with your yard or deck cleaning, then proPERLA® can lend a helping hand to you. Here’s how- You contact us with your cleaning needs and we will connect you with our professional applicator who will do the cleaning work for you. We’re looking for you on the other side.

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proPERLA® offers a range of exterior super hydrophobic waterproof paints & coatings designed to reduce energy costs and protect homes.

Through our official network of applicators, we provide services to end customers, ensuring the correct application of our products for your benefit.

Whether you are a professional interested in working with our products, or a customer looking for solutions, contact us for more information.

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