How To Identify and Treat Moss, Mould, Algae and Lichen

Moss, mould, algae and lichen aren’t just unsightly – if you’re not careful, they can also eat away at your walls, driveway, garden path, and other outdoor areas. If you’re one of the many Kiwis who suffer from mould growth inside the house, the health of your family is at risk from airborne infections.

But how do you tell which is which, and what can you do to treat them? Does moss require a different cleaning approach than, say, lichen? Let’s take a closer look.


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How to identify it

If you’ve ever gone walking through native NZ bush, you’ll have a decent idea of what moss looks like. It’s often bright green in sunlight, but duller in the shade. It’s dense, carpetlike, and soft to touch. Although it can look quite nice on a tree, it’s terrible on driveways or paths because it’s extremely slippery when wet.

How to treat it

Moss thrives in damp conditions. The best way to avoid it is by ensuring that all parts of your home and garden get plenty of sunshine and air. Of course, this isn’t always possible – so it’s important to know how to get rid of it when it occurs.

A simple of mix of baking soda and vinegar is sometimes enough to get rid of moss. There are plenty of harsher chemical solutions out there, but these tend be bad for the environment and unsafe to use at home unless you know what you’re doing. A third option is to use a pressure washer. Again, this is best left to the experts. Although it can be very effective on concrete in particular, a poor technique risks damaging the surface.


How to identify it

Black mould, green mould, brown mould, and yellow mould often grow in areas of low sunlight, and they’re the most likely of the four organisms to grow inside your house. Black mould in particular can be deadly if left untreated, but all types of mould can cause airborne illnesses or sneezing fits. When it stains your wallpaper or your ceiling, it often looks like dirt or marks rather than something that’s alive.

How to treat it

First, using a dehumidifier will help prevent mould from growing in the first place, by reducing humidity. Keeping your interior airy, dry, and sunny is a big part of the solution. For more stubborn mould, you can try using a solution of chlorine bleach and water.


How to identify it

Green algae is slimy, slippery, and smooth. Like many growths, it tends to be found wherever there’s plenty of moisture and a lack of sunlight. For New Zealanders, this is often the south side of your home (or the north side, if you live in the Northern Hemisphere). It can be quite hard to distinguish from moss without training.

How to treat it

Chlorine bleach mixed with water can be an effective remedy for algae on concrete and brick surfaces. Pressure washing can be very useful in these cases too – but again, we don’t recommend doing this yourself unless you’re trained to avoid damage.


How to identify it

Lichen often has a very distinctive appearance, though it can vary in terms of shape, size, and colour. It tends to be paleish, and has a scaly, flaky texture. It loves to grow on stone and concrete, and is notorious for eating away at the surface it covers.

How to treat it

For tougher surfaces like stone, you can use a pressure washer at a shallow angle to uproot the lichen. For softer surfaces, you can remove it with a scraper. It’s backbreaking work, but ultimately worth it since lichen takes such a long time to grow back.

Don’t want to break your back?

If you want to save loads of time and strenuous effort, consider hiring a professional to get rid of all your property’s moss, mould, algae and lichen in one go. We know when to use a pressure washer, when to use an eco-friendly chemical solution, and when to rely on a soft wash. We always ensure that the growth is effectively removed without causing damage to your property. Contact us today for a free, no-obligation quote anywhere in Auckland.

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