When used annually, Patio Black Spot Preventer will prevent re-infestation of black spots after they have been removed with our Patio Black Spot Remover.

Patio Black Spot Preventer will also prevent patio black spot infestation on new terraces.

It specifically targets the black lichen spores, killing them before they can germinate, avoiding the use of harmful and impractical pesticides. Patio Black Spot Preventer will also kill green and red algae that grow on garden paths, patios and other decorative stonework.

Prior to use, sweep the surface to remove any loose grime and dirt that may protect the lichen from treatment by the Patio Black Spot Preventer.


Ensure this product does not come into contact with fabrics or furnishings.

  1. Fill a pneumatic garden sprayer (Hozelock 5 or 7 Litre) with 3 Litres of water / 1 Litre of Patio Black Spot Preventer. (3:1).
  2. Pressurise the sprayer.
  3. Apply the product to a dry surface, as a fine mist and saturate the surface.
  4. DO NOT EXCEED 5 square metres per litre (once diluted).
  5. Allow to cure – DO NOT WASH OFF – the preventer will kill any sports that have landed in the last 12 months and green algae will disappear within days 3-5 days, without the need to pressure wash.

2.5 Litres of Patio Black Spot Preventer will treat 50 square metres (5M x 10M). Use annually for complete protection, where any green algae appear during the year, around the down pipes and drains, treat locally. You do not need to treat the whole area.

Say goodbye to constant pressure washing. Once you’ve used our Patio Black Spot Remover, an annual application of The Preventer is all you need to keep your patio looking its best long term. It doesn’t even need spraying off!

Ensure this product does not come into contact with fabrics or furnishings.

  • For use on all types of stone.
  • Dilute 3:1 (Water / Preventer).
  • Apply with a 5 or 7 Litre pump up sprayer.
  • Kills black lichen spores before they can germinate.
  • Algae disappears within 3-5 days.
  • Removes the needs for power washing every year.
  • Offers complete protection when used annually.