Washing machines are a very easy place for mould to grow. Mould spores tend to float around in small numbers all the time, like dust. But all they need to congregate and start growing is moisture, warmth, darkness and “organic materials to eat”, according to the experts at Cleaner Guys. Washing machines usually have all of those. They’re dark, wet, and warm, and can contain dirt and food particles that feed mould.

As mould removal professionals, they said that their top recommendation for cleaning mould out of a washing machine is hydrogen peroxide. Unlike many cleaners, the experts do not recommend using bleach to clean a washing machine. While it can do a thorough job, bleach is far more toxic and harsh compared to hydrogen peroxide, which “does just as good of a job”. 

Bleach is also risky because if you mix it with another chemical, it could produce toxic gas. For example, if you mix bleach and vinegar, they will produce chlorine gas.

Another problem with using bleach on mould is that bleach is a water-based product. After application, the pH will eventually neutralise, leaving behind nothing but more moisture, which is how mould grows in the first place.

When cleaning mould, households should make sure to wear sturdy cleaning gloves and a shirt with long sleeves.

Next, add hydrogen peroxide, and run your washing machine through a cleaning cycle, at its hottest and longest setting. 

One cup of hydrogen peroxide should be enough, but if you want to be extra thorough or your machine has a lot of mould, you can use two cups.

The solution should be added to the washing machine drum instead of within the drawer.

After the wash cycle, thoroughly wipe down the inside of the washing machine with a clean, dry towel and inspect it with your eyes and nose for any remaining mould residue or odour. 

After all this is done, leave the machine's door open for at least three hours to allow it to dry even more thoroughly. 

One mistake that can encourage mould growth in a washing machine is closing the door immediately after taking the wet laundry out, as this can prevent the machine from drying thoroughly.

It is equally important to check for mould around the outside of your machine. To do this, pull the washing machine away from the wall as far as you can, and visually inspect the floor and the walls around it for signs of mould growth.