Why is my plant’s soil mouldy?

Nobody likes mould. If you’ve spotted it – a fine, white dust on your plant’s soil – you may be concerned. Don’t be. It’s completely normal, usually harmless to your plant and very easy to get rid of. But it doesn’t look very nice, so you probably want it gone. We can help.

Mould lives in moist environments. Just as you’d find mould on mushy old vegetable or damp walls, you’ll find it on wet soil. It likes to grow somewhere that stays moist and doesn’t move. Your plants are more likely to grow mould if they’re somewhere with poor air circulation.

You can just scrape it off with a clean spoon. You don’t want to breathe it in, so wear a mask. It probably wouldn’t cause you any harm, but it’s never good to inhale mould. Spoon up all the mould you can see and put it in a bin outside. Then thoroughly clean the spoon.

There are a few simple ways to keep mould off your houseplants:

Don’t overwater. Don’t let your plants’ soil get too wet. Damp soil encourages mould. Only water your plants when the top two inches of soil feel dry.

Cinnamon. After you’ve scraped up the mould, sprinkle the soil with cinnamon. Cinnamon is a natural fungicide, so helps prevent mould growing. Bonus: smells great.

Keep your plants somewhere light and airy. Anywhere dark and stuffy will encourage mould. Mould finds it harder to grow in well lit spots with good air circulation. 

White mould is harmless. If you see grey mould, that can be bad for your plant’s health. 

Grey mould will have a dusty look and will often be on old parts of your plant, giving them a wrinkly collapsed appearance.

• First, isolate affected plants. You don’t want the mould to spread
• Cut off all the mouldy growth and dispose of it carefully, making sure it doesn’t come into contact with any other plants. Wash your hands thoroughly afterwards
• Move your plant somewhere dry and bright, though not in direct sun. Mould doesn’t like these conditions, so it will find it hard to return
• In serious cases, use a fungicide (always follow the instructions on the label)
• Keep an eye on your plant over the next few weeks to check the mould hasn’t returned

Finding grey mould is rare, so don’t worry too much. Follow all these tips and you and your plants should be living a happy, mould-free life.