A dish soap, like Dawn, is a safe place to start. The surfactants in dish soaps are designed to remove oil and grease, they're gentle enough to be used without issue on your pavers. In a bowl or bucket, mix the soap with water and pour it onto the stain and agitate. Rinse and repeat if needed.
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.
Use a Pressure Washer
If you have a small amount of mold or algae, you may find that the first two steps of drying out and sweeping the area is enough to remove it. If this is not the case, pressure washing is often quite effective in removing mold and algae from pavers, bricks or concrete.
Black spots and stains can appear on a variety of hard surfaces. From sandstone to concrete, resin, and paving. Pro-Kleen can be used to swiftly remove black stains. The black stains on your patio are normally black algae or lichen.
Patio Black Spot Remover is currently the only product developed specifically to safely remove those hideous black spots and restore the natural colour to garden stonework. Patio Black Spot Remover for Natural Stone will remove black lichen from all types of natural stone, including green algae and white fungi.
Sanding and chiselling will leave unsightly marks on your paving, bleaching can work well but you have to be careful not to kill your plants and dilute your bleach to the correct level, some people recommend using this method only in the winter months to avoid damage to plants but you still need to be really careful ...
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.
Remove those ugly green and black mold stains on your deck with Wet & Forget Xtreme Reach™ Hose End. Spray your wood or composite deck with Wet & Forget no-rinse cleaner. Allow the surface to dry (4-5 hours). Let Mother Nature do the rest of the work for you!
Mix equal quantities of apple cider vinegar and water in a bowl. Stir well and apply on the dark spots. You can also trying mix a few drops of lemon juice with the vinegar.
Patio Magic contains a fungicide that will kill off the following: Lichens (mostly black spots, sometimes white, on patios, concrete and blocks). Mould. Algae.
Similar to cleaning pavers with muriatic acid, avoid an intense concentration of bleach, as it can damage the pavers.
Whilst vinegar will not directly dissolve concrete itself, but it will degrade the cement that binds your concrete slabs or flags together. Extended exposure to vinegar will also cause any polish or sealant on your pavers to erode over time, leading to bleaching, stains and weathering.
Apply Black Spot Remover Plus with a pump-up sprayer or watering can (make sure you rinse out the sprayer or watering can afterwards). Flood the surface, the surface of your patio should be visibly wet. Make sure you spread the black spot remover over the surface and then leave it to dwell.
Whether your patio is sealed concrete or cement, or even sealed concrete pavers, a bleach and water solution makes it easy to clean away built up soil, stains from leaves and pollen, mold, mildew and algae.
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).
'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.
Because hydrogen peroxide has very strong bleaching properties, it can lighten dark skin areas such as dark spots caused by sun damage, aging, scars or hormonal changes. However, this process will irritate and destroy the user's skin a lot.
Wash patio slabs with white vinegar
This eco-friendly solution is made up of equal parts vinegar and water, which is then left to soak into the patio to correct any discolouration and also remove tough marks. You should first move all plants and furniture out of the way, then sweep the area to remove any moss.
Once what's causing the dark spots or patches is found and stopped, fading can take time. A spot that is a few shades darker than your natural skin color will usually fade within 6 to 12 months. If the color lies deep in your skin, however, fading can take years.
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.
Let the solution sit: Allow the bleach solution to sit on the patio for 10-15 minutes. This will give it time to break down any dirt and grime. Rinse the patio: Use the garden hose or pressure washer to rinse off the bleach solution, starting at the opposite end from where you applied it.
How to Use Pro-Kleen Black Spot Remover. Apply the solution neat using a pump sprayer or a watering can. Leave for a minimum of 2 hours or overnight if possible. Keep children and pets away from the area during this time.