Composting - Pest Problems and Prevention

Some composting pest problems are major, some are minor. It seems to be that all gardeners have issues with their composting at some point. It’s certainly a topic that regularly comes up during gardening lessons. To the extent that people have given up on their home composting; which is a great pity.

In this article, we’ll look at some of the garden pests most likely to be causing a problem. And more importantly, some solutions for you to put into practice.

When I wrote the first draft of this article it came to well over 2500 words! I thought you might find that a bit long for a quick read whilst you drink your coffee, so I’ve stuck to more general solutions for you. But I will follow up with another blog – and possibly put it altogether as a fuller range of compost bin pest problems and prevention in a short eBook for you to download and dip into at leisure.

Composting – Pest Problems – the Candidates

So what sort of pests are we talking about? Those that prevent you from using the compost in your bin. The creatures listed are not all garden pests in the wider sense but we’re looking from the perspective of whether or not you can use the compost in your compost heap. The ones I’m asked about most often, in alphabetical order, are: –

Ants
Bees
Foxes
Hedgehogs
Mice
Rats
Snails
Slugs
Wasps
Worms

Not all these creatures are garden pests in your compost heap. Ants, bees, hedgehogs, most slugs and worms are not what I would describe as pests in the same way that the other creatures are. They’re included here as new gardeners in particular (and some more seasoned ones too, truth be told) have a tendency to freak when they find anything other than worms in their compost bin. Indeed, I’ve even known worms to cause panic amongst novice gardeners, which is why I’ve included them too.

Composting – Is the Creature a Pest?

The following list contains those creatures which are not necessarily a pest in your compost heap:

Ants
Bees
Hedgehogs
Snails
Slugs
Worms

However, bees and hedgehogs hibernating in the compost and building a nest there can become a problem as it will prevent you from using the compost.

An ants’ nest in your compost heap does not prevent you from using the compost, but I appreciate you may not want to spread that compost onto your no-dig raised beds! If you regularly dig over the soil where the compost will be spread, then it is less of an issue.

Ants, bees and hedgehogs will build nests in undisturbed compost heaps, so you may find them in an old, unused compost pile. I operate a live and let live policy with these guys and would rather start a new compost bin than disturb them. If you don’t have the room for that, then read below for some solutions.

Snails, slugs and worms are creatures which you should hope to find in your compost bin. They perform a vital role in the decomposition process.

bees at entrance to beehive, walled garden

ant on leucanthemum close up, original photo by kie ker

Compost Bins – Is this Creature a Pest?

These guys would come under the definition of pest for the majority of gardeners who found them in their compost heap:

Foxes
Mice
Rats
Wasps

Why did they get there? Probably because the compost bin had been left undisturbed.

Foxes, more specifically vixens, will be looking for somewhere to create a den in which to raise their young. A warm compost pile is easy digging. Mice will use compost bins to hibernate in and also to build nests.

One method for removing rats and wasp nests from your compost is of course to call in a pest controller. It is possibly the safest option for many of us.

But as for preventing these pests in the first place and reducing the likelihood of their returning, read on for tips.

ground elder flowers, pollinating wasp, Aegopodium podagraria

Composting – Pest Problems and Prevention

The key things to achieve are prevention and dissuasion. I know its sounds obvious, but people do forget. Remember that the more difficult it is for pests to enter, the less likely they are to try to make a home in your compost.

Lets look at this in relation to the compost bin and then to the compost.

The compost bin

The simplest preventative measure is to ‘visit’ your compost bin or compost heap regularly. This is because an undisturbed heap allows pests to settle in and build nests. The visit could be adding plant material, turning the compost or removing some to use in the garden.

If your compost bin is standing on soil, it generally helps if you can move it onto a hard surface of flags or similar. Where that’s not possible, a short-term alternative is to place a thick layer of semi-permeable membrane underneath to prevent pests entering from below.

Adding 1/4-inch wire mesh around the base of a closed compost bin helps prevent tunnelling in. This is a good option where you want to keep the compost bin on soil. Be sure to wrap the wire around the bottom lip of the bin as well, to prevent gaps. For open wooden compost bins, also line the sides with mesh, and add a lid with mesh.

The Compost

Keep the compost damp. Most of these pests like a warm dry location. Ensuring that the compost is damp, whether it’s in use or not, will help prevent them.

In the autumn, spread your compost over the soil and garden borders. That way, there won’t be a warm place for many of these creatures to hibernate in. Overwinter is when many will establish themselves in the compost. In all fairness, you’re probably adding less in the way of plant material so theres less disturbance.

If you add more food waste than plant / garden waste it may be encouraging certain types of pest. Rather than stopping, run a bokashi system alongside your general composting. This can take your food waste and contain it safely.

On a wildlife friendly note you could create alternative habitats for some of the compost bin pests. For example, hedgehog houses, bug hotels, a suitable heap for wild bees to overwinter.

And finally

For more help with your compost, tips about the different types of composting and compost bins, you could download the Plews eBook

But if you’d prefer hands-on personal help from yours truly, with a mix of practical sessions and theory in our bespoke Gardening Lessons and Courses check out the blog link below plus link for the pdf download with more info

For further gardening advice and inspiration, ideas for pest resistant gardens and more, check out Plews Potting Shed blogs, including the selection below and our monthly Tipsheet You could also come and find us on Instagram Pinterest and Facebook

And on that note, you can have a peek at the progress of my garden renovation, Spitfires and Slow Worms, on Instagram and Facebook You may even get to see it in person later this year / early 2025 as I’m planning a couple of workshops. I had hoped to do that already but house renovations have been as big a thing as garden reno so there hasn’t been the room. Keep an eye on the website and social media for an update.