Why does my patio go green?

If you have a patio, chances are you will soon be making the most of it as summer rolls around and so you will want to make sure it’s in good condition. However, a common problem with patios is that they can become discoloured and slippy due to algae, mould, mildew and moss growth. Algae, moulds and moss on your patio will look unsightly and can be a recurring issue. So, to help you keep your patio safe, attractive and welcoming, we’ve put together some handy patio cleaning and moss removal tips.

What causes my patio to discolour?

If your patio has patchy discolouration which is green or black, this is probably algae, mould or mildew growing. These growths are natural and won’t really harm your patio itself, although they can make it slippier and keep it from looking its best.

Algae, moulds and moss like shaded and damp conditions. Unfortunately, England’s climate affords quite a lot of damp weather and so if your patio doesn’t get much sunlight, or is being shaded by plants, this creates favourable conditions for problem growths. They only need a very small amount of water and food – which can be anything from organic debris to minerals – to grow, making it hard to cut off sustenance.

How to get rid of patio algae, mould and moss

Before you reach for the nearest industrial strength moss and algae killer, you should consider other helpful methods to remove growths from your patio.

  • Does water drain away from your patio well? If not, you may want to consider incorporating better drainage solutions – poor drainage could be keeping the area excessively damp
  • Cut back plants which are shading your patio to ensure the surface can stay dry as far as possible
  • To remove moss from your patio, the easiest method is simply to dislodge it with a screwdriver, knife, or similar

If you haven’t managed to control your algae or mould problems, using specially designed patio cleaning chemicals, amongst other techniques, can be a great way to restore the look of your outside space.

  • Whether you brush down your patio to discourage initial growth, or you’re using a broom to improve the action of a cleaning solution, choose one with stiff bristles for the best scouring results
  • There are many patio algae removers available – try to choose one which is suited to your patio material, for example coloured concrete blocks or natural stone, and always follow the product instructions
  • Use harsh chemicals sparingly, you don’t want excess product to damage plant life surrounding your patio
  • Pour a small amount of sand into any paving joints to discourage moss and weed growth
  • If you do decide to power wash your patio, be careful not to use one with too high a pressure as this can be damaging to your patio surface

How to prevent patio algae, mould and moss coming back

The reoccurrence of algae, mould and moss can be frustrating but, if you have done all you can to keep the area well-drained and unshaded, ongoing maintenance is your only option. Regularly brushing the surface can dislodge growths and discourage them from getting a hold on your patio. Applying a solution of copper sulphate crystals dissolved in water can be a good way to prevent growth but, like algae removers, will need to be periodically reapplied.

UK Surfacings Ltd have a team of skilled operatives who can carry out top quality surfacing work for both domestic and commercial clients. Our experience and knowledge means we can provide a variety of surfacing options, from block paving and indian sandstone to tarmac and resin-bound. For surfacing enquiries in and around London, Croydon and Surrey, don’t hesitate to contact our helpful team.