How To Remove Moss from Concrete

Got a stubborn case of moss on your concrete? Moss can be unsightly, especially as it builds up.

Maybe you’ve tried several off-the-shelf solutions, and they’ve let you down, or you simply want to make your (or a client’s) outdoor spaces look amazing? To achieve that, you’ll want a product that’s tough enough without damaging surfaces.

Luckily, our FACTS-and-BASIS-qualified advisers have a wealth of experience with all aspects of chemical spraying and surface cleaners and are here to help.

Read our guide for tips on how to treat moss and keep it at bay. Whether you’re looking to treat a concrete path, patio, roof or driveway, these tried and tested tips by the gardening professionals will show you how to remove moss from concrete.

First things first, you’ll want to make sure you’ve got the right products and equipment to do a proper job.

With AlgoClear, moss will start to decay quickly. Any remaining residue will be removed naturally by the wind and rain. The best part? The thorough clean provided by AlgoClear combined with the fact that moss is very slow growing means that it can take in excess of 10 years for moss to return.

AlgoClear needs to be applied as a diluted spray. If applied as part of a professional service, we recommend the AlgoClear delivery system and the 5m telescopic lance. The lance can be fitted with both the scraper head and sprayer brush head. For ground and low-level spraying, the 1.8m lance is more suitable. For domestic use, use a backpack sprayer fitted with a high volume nozzle.

1. Make sure you're confident it's moss
   Correct identification of the growth or staining is important to ensure that the correct product is used. Moss is often clearly distinguished from other plant matter, as they don’t have roots and appear as soft yellow or green clumps. In comparison, algae appears as a slimy, green film on concrete. AlgoClear is our recommendation to clean moss and algae.
2. Protect surrounding areas
   This will not only protect plants from spray drift but also speed up the clearing process. If treating roofs, gutters should be covered with plastic flashing, and downpipes should be blocked. Balls work well for this.
3. Brush away large clumps of moss or leaves
   AlgoClear can remove even large clumps of moss. However, they must be thoroughly drenched, increasing product usage. If this is not done, large clumps may be able to regenerate. That's why we recommend brushing away vegetation and larger clumps before applying the product.
4. Dilute the AlgoClear
   As per the guidelines for the surface being treated, you'll need to dilute the product. Alternatively, you can set the AlgoClear delivery system to the correct dilution rate:
   -Concrete roofs: Approx 1ltr per m2
   -Concrete renders and walls: Approx 0.5ltrs (500ml) per m2
   -Concrete ground surfaces, such as pathways and driveways: 0.25ltrs (25ml) per m2
5. Spray the surface

AlgoClear works best when it soaks into porous surfaces, such as wood or concrete roof tiles. The weather lifts AlgoClear and washes the surfaces continually over several months. We recommend a treatment every 1–2 years, wherever you have the conditions for moss and algae growth.

Moss enjoys damp, shady conditions and reproduces by spores rather than seeds. So, wherever you have areas that lack sunlight and are exposed to rainfall, it’s worth watching out for moss growth. Giving your concrete ground surfaces a regular sweep helps remove debris that would otherwise block the sun.

Follow these steps, and you should be able to effectively treat moss on your concrete walls, roofs and ground surfaces. Shop our moss control products today or read more of our expert guides.