Compost Magazine

Composting tips, advice and science.

A group of rats peer out from a hole in a pile of compost.

Rats In Your Compost? Here’s What to Do…

I didn’t scream. 

Honestly. It was more of a gasp. 

(A manly one, I might add. A claim I can make in the confident knowledge that I was the only person at the bottom of the garden.)

I’d opened the lid to my compost bin, and there was a humongous rat staring at me. 

It was the first time, but it certainly wasn’t the last! 

Sometimes there were two or three. Sometimes they were as shocked as me and bolted for the hole they’d just made. Other times they stared at me before languidly heading towards the exit. 

I’ve written about mice in compost bins before, but they never have the same impact on me. Both can spread diseases – both will steal your beans and peas. But somehow, rats come with a fear factor that mice just don’t have. 

If you’ve landed on this page, chances are you have either had the same problem or are worried about experiencing it. So here’s a quick primer on why your compost is so attractive to furry rodents, how you can reduce the chance of attracting them – and what steps to take if you do get them!

Rats love compost heaps – here’s why…

Compost heaps are (often) warm places. They are easy to burrow into, and contain delicious (for a rat!) foods into the bargain. 

Kitchen scraps often offer easy pickings for rats. However, even if you don’t compost kitchen scraps, the rodents will find plenty to eat. In fact, a rat’s regular menu includes worms, slugs, reptiles and even mice. 

There is plenty you can do about them, though. The first thing is to minimise the attractiveness of the compost heap, in the hope that when they are passing through, they move on to a more attractive proposition.

Secondly, when you do have rats, you can take action to kill them. The word kill is not nice, but this is an animal which can spread serious diseases.

They’re also intelligent and social animals which will avoid actions which cause suffering to other rats. That means the best option is always deterrence – so that’s what we’ll start with. 

How to deter rats from compost

Keep the compost hot

A compost heat steams in a beautiful garden.

While there is always food around for rats, kitchen scraps – especially cooked food and meat – present a particularly tempting target. The smell of these foods can carry a long way, bringing all the rats in the area in. 

One way to deal with that is heat. If you construct your compost heap well, or use an insulated bin, the thermophilic temperatures will break down food scraps quickly. Indeed, if you get the compost hot enough, it will deter rats from burrowing into it too.  

It’s not a 100% solution, as eventually compost will cool down, and you need to let it mature before you use it. (It’s a lot harder to do in winter too, given the lack of ideal compost material and the far-from-ideal weather many of us experience.)

Even if you do have hot compost, it’s a good idea to bury food scraps. As you go deeper into the compost it is hotter – which means the microorganisms are at their most active, and will break down the food faster. And, of course, it prevents the tempting smell of rotting food from drifting to the sensitive nose of rats. 

Avoid wet and soggy compost heaps

When compost gets too wet, it can switch from aerobic (with air) to anaerobic (without air) composting. 

Anaerobic composting causes more smells to be released, which in turn can attract rats.

This also ties into the previous point. While the bacteria that breaks down organic material fast require moisture, too much stops them from getting oxygen. Once again, a slower breakdown process gives food more time to rot down, release odours and attract rats. 

Turn your compost

Another tip is to turn your compost regularly. 

This helps in two ways. First, it maintains the heat in the compost pile, and as we’ve seen already that helps deter rats. Secondly, by regularly disturbing the heap you are making it a less attractive place for rats to make a home.

Limit what you compost

I’m all for composting as much as you can, but if you don’t have a hot heap it might be worth excluding kitchen scraps. 

It doesn’t have to be all-or-nothing, either. You can limit what you compost when your pile is not hot, and expand it when it is hot. I’ve composted dead chickens in the summer when my pile has been steaming, but wouldn’t dare right now in the middle of a miserable, wet January. 

Rat proof your compost pile

Another option is to wire up your compost pile or bin. 

This is one we have covered before in our mice-prevention tips. However, this is an easier step with rats, as they are larger and have less ability to squeeze through truly tiny spaces. 

Bear in mind you have to wire up the base, the sides and over the top. You also need a strong wire they can’t chew – something like a 16-gauge to 19-gauge galvanised wire. It may well be worth buying wire specifically designed to stop rats.

You can also place your bin on concrete. I wouldn’t suggest going so far as to actually lay concrete, but if you have some in your garden already you could put your bin on it. This will stop them from burying through from underneath.

Get a rat proof compost bin

I have a HotBin, and while it’s superb for getting hot compost, it’s definitely not rat proof!

The Green Johanna bin is one which is  supposed to be rat proof. (While it’s on my list, I haven’t tried this one out yet). There’s also the Green Cone composter, which is dug into the ground, although this is a digester rather than a composter. 

(Apologies to US readers, as these bins are currently only available in the UK.)

Feed animals and birds in the morning (or use a rat proof automatic feeder)

Rats may set up home in your compost heap, but it’s not always your compost heap that attracts them. Bird feed, chicken feed, rabbit feed and the like can all attract them into your garden. 

Rats are mostly nocturnal, although as they breed and get hungry they will learn to raid your animals’ food in the day. At the stage of prevention, though, ensuring there is no food left overnight may help deter them. 

I have stopped feeding wild birds completely.  (Partly for this reason, although there’s also research that suggests it’s not always a good idea to feed wild birds.) I used to try and ensure that my chickens were fed in the morning, and to feed them the right amount so it would be finished by night. I now use an automatic chicken feeder, which is great when it doesn’t clog up with mud!

How to control rats when they are already in your compost


Rat trap

I’ve tried several types of traps, including electric traps (for mice), live traps and kill traps. I’ve caught rats every time I’ve used traps – but while they do reduce the population, it never seems to eliminate them. (Friends around me echo this sentiment, so it’s not just me!) 

My family used live traps extensively when I was young, and we caught a lot of rats. However, I would suggest using traps that kill. If you use a live trap, you either have to kill them or move them. You can’t put them anywhere close to your house, or they’ll just come back. Unless you put them in the middle of nowhere, you are just transferring the problem (and potentially the disease) to someone else. 

Make sure you choose a large, heavy duty trap that is designed specifically for rats – the smaller ones risk the danger of injuring the animal without killing it. The traditional style rat traps – made of wood and metal – are good value and work fine. However, being clumsy I am always worried about catching my fingers in the trap. So I often use traps where you just push a lever down till it clicks. 

While cheese is often mentioned as a good bait, I find that peanut butter and chocolate work well when it’s dry. (Snickers, nutella and mars bars have all caught them in the past!) 

Do make sure that the trap is not in the open, or you will end up killing birds – you can either buy a container to house the trap or put simply a bucket over the trap with a stone to keep it down. 

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Animal Control

Another way to control rats is with dogs. Getting a dog is a big decision and comes with a lot of responsibility, so I’d never recommend doing this purely to control animals. However, if you’re considering it anyway, or if you love dogs, this might be an option. 

The thing to remember is that not just any old dog will do – you want one that will be a good ratter. For dogs, it’s hard to beat a terrier – Jack Russells are ideal. (Although my first dog, a Jack Russell crossed with who-knows-what, refused to get near them after being bitten once. Maybe choose a pure breed!) 

Ideally, you’ll ask around locally, and get a pup from a known ratter. Or, if you’re not ready for a dog, see if you can borrow one. 

Cats are excellent for controlling mice, but a rat is a different matter – and they are too big and scary for many cats. For rat control, you’re going to want a big, tough cat, and again I’d ask around locally to see if you can find a known ratter with a litter – and then choose the biggest kitten!

Ferrets are also supposed to be excellent for rat control. While I’ve never kept them myself, people around me say that rats are so scared of ferrets, they will move out of the garden as soon as you get one. On the other hand, while they can be very affectionate animals they can really stink, which is one reason I have never tried them!


Poison is certainly guilt inducing. One of the problems is that it doesn’t necessarily stop with the rat – it can pass on up the food chain.

I’ve heard people say rats take poison back to the nest, and this may be true. But I’ve also heard a friend say that after he put poison down the barn owls on his farm disappeared. 

(They may well have been due to mice dying – and they can certainly die in the open after eating poison.)

What’s more, rat poison has a very strong smell. I suspect this smell actually attracts rats from outside the garden.

On the other hand, it is the most effective solution for getting rid of rats when you do have them.

I do have a couple of tips for using it. First, as with traps, always ensure the rat poison is covered to ensure you do not kill other animals such as hedgehogs. A bait station is ideal for this, but a bucket with a stone on it will do if you don’t have one. 

Secondly, don’t just put bait down once and assume it has done the job. With bigger rats, it can take repeated doses of poison to kill them. The last thing you want is them developing immunity, which is an increasing problem in some countries.

Can you completely stop rats?

If you have a small compost area which is easy to wire, you can certainly deter rats. However, it’s hard to completely stop them all the time. 

Just as they have been for centuries or more, rats are never too far away. As you get closer to your garden and to nature, you come closer into contact with them. 

The steps I’ve outlined here will help deter them, keep them under control when they do appear and at times eliminate them. That’s about all we can do – you can never guarantee they won’t reappear. If you are concerned about disease, it may be worth wearing gloves – and, of course, always washing your hands after gardening.


Do compost bins attract rats?

Basically yes! Compost bins provide a warm, safe space that’s easily burrowed into, and they often contain food, whether it’s food you’ve added or naturally occurring. However, you can decrease the attraction by burying food to mask its odor, and following these guidelines to ensure your compost is hot enough to quickly break down food.

Can you use compost that has had rats in it?

Rats are everywhere, and we often don’t know if they have been around! So, whether we know it or not, we often use compost that has had rats on it. However, rats can cause some nasty diseases, so it’s advisable to use gloves when handling finished compost.

Do coffee grounds deter rats from compost bins and heaps?

No – or at least not unless you have huge amounts. I’ve certainly had to deal with rats myself despite regularly adding coffee grounds to my compost bins.

Indeed, some scientists have even managed to get rats to eat coffee grounds by replacing part of their corn with coffee grounds.

Does the type of compost bin impact rat attraction?

Absolutely. Compost tumblers, for example, are raised above the ground, making it difficult for them to gain access. Open bins and piles, on the other hand, make it easier for rats to gain access.

Does the type of composting impact rat attraction?

Yes. Cold composting means it takes longer for food to break down, which means that rats are more likely to be attracted to the compost pile. Pit composting, as long as the food is buried deep enough, rarely attracts rats.