It’s no secret that looking after plants can be beneficial to your mental health – but being a plant parent isn’t all sunshine and rainbows.
In fact, our leafy friends can come up against a number of not-so-pleasant issues during their lives, from fungus gnat infestations to leaf and root rot.
One of the most common of these issues is, of course, mouldy soil. If you’ve ever noticed white or grey fuzz making its way across the top of your plant’s soil, you’ll know what we’re talking about. It can often appear as if this mould comes out of nowhere, and it can be pretty persistent even if you scrape it off.
But there’s often a simple explanation as to why the surface soil can become mouldy – and it’s relatively easy to get rid of once you’re armed with the right tools and knowledge.
To find out more, we asked Richard Cheshire, Patch’s plant doctor, to share his insight. Here’s what he had to say.
Why is a houseplant’s soil so important?
First things first, it’s important to understand why taking care of your plant’s soil is so important. While a plant’s leaves and appearance may attract the most attention, its soil is integral to its overall health and growth.
“Soil holds all the minerals and nutrients a plant needs to survive and thrive in your space,” explains Cheshire.
“Good soil provides a happy home for your plants’ roots, a healthy ecosystem to support their continued growth, and just the right balance of moisture retention and drainage.”
What causes mould to grow on the top of a houseplant’s soil?
There are a number of reasons why mould might be growing on top of your houseplant’s soil – one of the most common being excess moisture.
“Mould lives in moist environments, so just as you’d find mould on mushy vegetables or damp walls, you’ll find it on wet soil,” Cheshire explains.
In this way, watering your plant too often (known as overwatering) can contribute to the growth of mould.
Putting your plant in a pot or soil medium with poor drainage (for example, a decorative pot without a hole at the bottom) can also cause mould to appear.
The location of your plant may also contribute to mould growth. “Mould will grow in places with poor circulation, as the lack of fresh air causes a build-up of moisture in the air,” Cheshire says.
Leaving decomposing leaves and other material on the surface of your plant’s soil can contribute to poor air circulation, making the problem worse.
Is soil mould growth bad for a houseplant?
While white mould isn’t necessarily a cause for concern, the appearance of grey mould can indicate a much bigger issue.
“White mould is harmless, but if you see grey mould, that can be a sign your plant isn’t in good health,” Cheshire explains.
“White mould will look fuzzy, while grey mould has a dustier appearance and will often be on old parts of your plant, giving them a wrinkly, collapsed appearance,” he adds.
How can you get rid of mould on a houseplant’s soil?
How you remove the mould depends on the type of mould you’re dealing with.
For white mould, things are pretty simple. “If your plant has white mould, you can scrape it off with a clean spoon and pop it in the bin,” Cheshire says.
“You don’t want to breathe it in, so wear a mask. It probably won’t cause you any harm, but it’s never good to inhale mould.”
If your plant is growing grey mould, you’ll need to take more drastic action, Cheshire says.
“If your plant has grey mould, isolate the affected plants, 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 and move your plant somewhere dry and bright, though not in direct sun.”
How can you prevent mould growing on a houseplant’s soil?
One of the easiest ways to prevent white mould from returning to your houseplant’s soil is using a natural fungicide you’ve probably got in your kitchen cupboard: ground cinnamon.
“After you’ve scraped up the mould, sprinkle the soil with a little cinnamon, which acts as a natural fungicide and will help prevent mould growing,” Cheshire recommends.
Because, as we’ve already discussed, mould typically grows in spots that are moist and have poor circulation, the key to preventing mould growth is to address these issues.
Indeed, as Cheshire explains, “You can prevent mould growing on your plants by not overwatering them, and ensuring they have plenty of fresh air and bright light if growing indoors.”
Images: Getty