A Black Spot Remover for Irish Patios

Black lichen spots are the curse of patios across Ireland. Our damp, mild climate gives spores the perfect conditions to take hold. Once they spread, ordinary cleaners rarely cope. That’s where Stontex Black Spots Remover earns its place in the shed.

Four Times the Strength of a Standard Patio Cleaner

This heavy-duty cleaner targets deep-set black lichen stains on stone, concrete, brick and render. It works at four times the strength of a standard patio cleaner, so you can apply it neat straight onto the worst-affected areas. As a result, you clear marks that would otherwise need hours of scrubbing.

How to Remove Black Spots From Paving

First, apply the cleaner neat onto dry, soiled paving. Next, work it into the surface with a stiff nylon brush. Then leave it for at least 30 minutes, or overnight on really stubborn staining. Finally, rinse thoroughly with a hose or power washer.

Coverage

One 5L bottle covers roughly 10–15m² when used neat.

Use It Safely

Because this product is caustic, use it outdoors only, and only on paving no higher than a garden wall. Keep it well away from windows and doors, since splashes could cause damage. Likewise, avoid grass and plants, and always rinse residue down the drain rather than across borders. Wear gloves and suitable clothing while you work.

Protect Your Paving Afterwards

Once your paving comes up clean, seal it to protect the finish and slow down regrowth. For Indian sandstone, use our Stontex Indian Sandstone Sealer. For block paving, choose Stontex Paver Plus. Then, to keep algae and moss at bay between deep cleans, use our Green to Clean spray-on cleaner.

Not sure which sealer suits your surface? Get in touch with our team in Letterkenny and we’ll point you in the right direction.

FAQs

What causes black spots on patios?
Black spots are usually lichen. It’s a slow-growing organism that roots into the surface of paving, which is why ordinary patio cleaners and power washing often can’t shift it. Ireland’s damp, mild climate makes it especially common.

How much do I need?
Each 5L bottle covers around 10–15m² when used neat. So for a 30m² patio, you’d need two to three bottles, depending on how heavy the staining is.

Will this damage my grass or plants?
Yes. This cleaner contains strong fungicides that kill organic spores in stone, so it will also harm grass and plants. Apply it carefully, and rinse any residue down the drain, well away from borders and lawns.

Is it safe for me to use myself?
Yes, as long as you take sensible care. The product is caustic rather than acidic, so it can irritate the skin. Wear gloves and suitable clothing, and if any splashes onto your skin, rinse it off thoroughly straight away.

Should I seal my paving after cleaning?
Yes, we’d recommend it. Sealing protects the surface and helps slow down future regrowth. Simply choose the correct sealer for your material.

What surfaces can I use it on?
Stone, concrete, brick and render. However, only treat external paving no higher than a garden wall, and keep it away from windows and doors.