Don’t reach for the bleach when slippery green slime is making your deck dangerous and your patio perilous. Modern cleaning methods such as soft washing are more eco-friendly and are super-effective.  Read on to find out how to clean algae from decking and patios. One of the joys of living in Ireland is that the mild climate and high rainfall encourages plants to grow. When it comes to my favourites – lawns – that’s a good thing. However, it’s not so great when greenery grows in the wrong places. Green algae is great in the sea – in fact it produces something like 70% of the oxygen we breathe. (It also gives the sea its characteristic smell). However, when it’s on your path or your rendered walls it’s unsightly and potentially dangerous.

What is algae?

Just like any green weed, before we can fight it, we need to understand it.  Algae usually looks like green slime although there are varieties that appear red and others that look like soot. It’s actually like a mini-lawn. Whilst a lawn looks like a continuous green covering (at least the ones I look after do); it is in fact millions of individual plants. Likewise, the green slime you see on your path is made up of millions of single-celled plants that form a living film (aka biofilm) on the surface.

How NOT to get rid of algae

Some herbicides will kill grass permanently, some will knock it back temporarily and some won’t touch it. Ditto for algae. While some chemicals can get rid of it for the longer term, others just make it sick for a while. Bleach falls into the second category. It seems like the ideal solution for green slime – blast it with bleach and wash it away. When you look at the science though it’s not such a good idea. To start with, any liquids you pour onto your garden will filter through the soil and have the potential to end up in streams and rivers. Nasty. Plus, bleach residue breaks down into the salts that algae feed off – so you are actually making the problem worse in the long run. Bleach isn’t a great cleaner for decking or timber. It really can do a lot of damage to the surface. Breathing in bleach fumes is not really good for you either.
steps with algae before treatment
Slippery steps before algal growth was removed
steps with algae after treatment
After treatment – in my book the safety rating has improved enormously

What will remove algae effectively without damaging anything?

In my own garden and for some of my clients, I like to use a softclean product to get rid of the biofilm formed by algae. Softclean doesn’t mean I’m attacking it with a velvet cloth.  It means that the cleaning fluid is biological and is incredibly gentle to everything except algae. It certainly won’t damage lawns or soils – which is important to me. Softclean is applied with a special sprayer. It has a long arm so that when I need to, I can reach roofs, walls  etc. The chemical is suitable for stonework, render, timber, tarmac and even artificial grass. It brightens up garden ornaments, planters and furniture and can be used on plastic toys too. It will sometimes take a couple of days to work – but then long term solutions never seem to be instant. There’s no scrubbing or powerwashing needed with Softclean. Which is a real bonus on driveways, patios and rendered walls because in the wrong hands, a power washer can dislodge mortar.

Help with removing algae from your home and garden

Premier lawns offers a softclean service in Belfast and the surrounding villages. If you’d like help to control green slime on your decking, patio or rendering, please don’t hesitate to give me a call. I can come to you to explain more about the process and give you a free, no obligation quote. Get in touch with Robbie today

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