Vinegar is a safe and effective mold removal solution, but if this method doesn't prove to be effective, then a heavier-duty weapon may be deployed: bleach. One cup of bleach mixed with a gallon of water should do the trick. Simply combine the bleach and water in a spray bottle and apply directly to the pavers.
If you have greenish-black stuff on your concrete patio, it's probably mold, mildew, or moss. Damp or moist conditions from rain or humidity can encourage mold and mildew to grow in those nooks and cracks of concrete pavers or bricks.
Simply put, black stains on flagstones are caused by certain types of mold and mildew. These fungi find their way onto the stones either from their spores landing on the stones or from simply extending onto the stones from patches of mold or mildew right beside them—a pretty common occurrence for garden pavers.
Vinegar or baking soda: These natural cleaners work well to clean cement patios with stubborn charcoal or rust spots. Mix equal parts vinegar and water, scrub the patio with the mixture, then give it a good rinse. If stains don't dissolve, try undiluted vinegar.
If your concrete has ugly charcoal-gray or black streaks or splotches, black algae is probably the culprit. Black algae can grow on many outdoor surfaces such as concrete or roof shingles and will thrive as long as there is moisture and sunlight.
Experts say they can do the trick for the patio as well. 'You can remove black spots easily from patios in an eco-friendly, low-cost way, with white vinegar,' says Laura Harnett, Founder, Seep. 'It has antifungal and antibacterial properties and will also stop the mould or lichen growing back.
Cleaning your pavers with bleach has a lot of benefits: Disinfecting the Surface: Bleach is an effective disinfectant and can kill any bacteria or mold on the surface. This will help to prevent any health hazards from occurring. Removing Tough Stains: Bleach is also effective in removing tough stains from the surface.
Try Concrete Stain
The simplest path to reviving tired pavers is to apply an acrylic-based semitransparent concrete stain, such as Behr Premium Semi-transparent Concrete Stain ($27/gal.; Home Depot) or Valspar Semi-transparent Concrete Stain ($28/gal.; Lowe's).
Once again, acetic acid will wreak havoc with your block paving. Porous stones like limestone and sandstone are more susceptible to damage than most, as the vinegar can seep into the stones themselves, though even sealed and non-porous stones can discolour and bleach.
Water and mild dish soap is a popular cleaning solution because it's easy to find at home and it won't damage brick, but it will tackle stains. The BIA recommends using hot water for surface cleaning with a detergent. White vinegar and water, another common household cleaner, can also be used on mildew.
This is a common problem. It could either be mildew, or a reaction from tannin in the wood. Given that you have black residue on rocks, it may be mildew.
Porous paving slabs allows rainwater to soak in the porous surface and are a hotbed for lichen stains and black spots to take hold on your patio. Fortunately this problem can be easily rectified with a good cleaning product. It does not need a professional cleaner to clean it off. You can DIY with Black Spot Remover.
To clean paver slabs, you can use a detergent, such as Dawn, or a vinegar-water solution that is gentle enough to effectively clean without causing damage to your concrete pavers.
OxiClean is a powerful concrete cleaner that works well on various materials, including pavement and grout. This concentrated solution provides excellent cleaning without leaving residue.
Although bleach is great at the whitening effect, you can use peroxide to achieve this. Hydrogen peroxide is an oxygenated bleach. It is safe for plants, so when you rinse this solution, it won't harm anything. It works together with the dish soap and baking soda to remove dirt and whiten dirty concrete.
Apply Paver Sealant to Enhance Faded Pavers
Once the pavers are dry, you can see what they look like in their clean state. If you're content with the appearance, you could stop there. If you still think they need to be enhanced, you could use paver sealant to bring out the color of faded pavers.
Bleach: This alkaline solution may be effective for other household uses, but it can discolor concrete pavers that have been colored or stained.
There are useful tools for cleaning paving stones, such as joint scrapers, sweepers, and pressure washers. In addition, pavers can be cleaned with a small pickaxe, broom, and garden hose.
Baking soda is an amazing household cleaner, and it can work really well on your pavers too.
Dry brushing with or without application of clean sharp sand. OR High pressure water jetting with or without detergent. OR Apply fungicides. Use ordinary bleach or calcium chloride followed by sodium hypochlorite dissolved in water (1kg in 5 litres) then scrub with stiff brush.
Combine 1 teaspoon of hydrogen peroxide and 1 teaspoon of milk in a glass bowl. Dip cotton pad or Q-tip in the bowl and apply to dark spots. Leave on for 15 minutes. Rinse with lukewarm water and finish off with your favorite serum and moisturizer.
To clean your pavers with vinegar, mix equal parts of water and vinegar in a bucket, let it sit on the pavers for an hour so that the vinegar has time to work, then scrub the surface with a brush or a sponge. Make sure you choose white vinegar for household cleaning, as other types of vinegar can stain.