Patio black spots are a type of lichen that embed themselves deeply into the hard surface.

Notoriously more difficult to clean than patio moss and algae, these blemishes can withstand even the most rigorous pressure washing, leaving many to wonder if a truly effective solution exists.

Fortunately, gardening enthusiasts have taken to the Mrs Hinch Gardening Tips Facebook page to share a few of their trip and tested methods.

One of the first recommendations was to use sodium hypochlorite which is a solution that acts as a powerful agent against lichen, effectively killing the organisms responsible for black spots.

Cassandra said: “Sodium hypochlorite cleared mine. Sprayed it all over my patio, left it half an hour then just rinsed off. Leave longer if you prefer.”

David Simkins wrote: “Sodium hypochlorite from eBay. Just brush on and rinse off after an hour. It will kill any weeds too.”

Charlotte Lodge commented: “Sodium hypochlorite worked so well for me to get the black spots off.”

Sodium hypochlorite retails for £21.50 on Amazon or from Alliance Online for £30.

However, one gardener claimed that sodium hypochlorite doesn’t entirely remove the black spots, it just causes it to fade.

Shannon Booker explained: “Sodium hypochlorite is undiluted bleach which is really good at cleaning any paving. 

“I  have used it past and present but it doesn't remove black spots it just fades it. It is a fungus embedded and grows I have it on Indian stone.  

“This year I have used the Pro-Kleen black spot remover and the stains have all gone now.”

Other gardening fans also recommended this product. Jess Gwyen said: “Pro-Kleen black spot destroyer it's really good.