10

I've found a rat this morning in my compost bin :-(. It burrowed into in.

It's a small compost bin with solid plastic sides, a lid with an open bottom. In retrospect it was a potential rat haven. It was next to a fence and I was storing paper behind it (a.k.a a lovely rat home). I've moved it about 2 feet away from the fence and got rid of the paper. Is there anything else I can do? I want to keep the bottom at least partially on the ground to let the worms in. I was thinking of digging a hole about 30 cm down and putting the bin into that. Will rats dig down that deep?

Anyway - all answers gratefully received

  • 1
    The screen you use HAS to have openings no larger than 1/4inch. This is the size rats are unable to chew. If you are using any rat traps or poison you'll kill your natural predators. Cats and dogs need to be indoor animals. Just the presence of a dog in the yard deters rodents. Cats if allowed out of doors become the entire neighborhood's cat. I would entice one of the roaming cats to hang out in your yard on their neighborhood route. No traps or poison of Lily type plants. We live off grid and feral and strays found our home. Got em all fixed: 4 inside and 12 out side. No rodents. – stormy Oct 2 at 9:44
  • And you want oxygen in your compost, do not bury it...very stinky and not good compost. – stormy Oct 2 at 9:46
5

The model of compost bin I use has an optional rodent-screen that you place on the bottom. This is meant to solve exactly this problem. Having used this approach for about a 1.5 decades, I would say success is mixed.

There are a few major problems I run into with this:

  1. When using a shovel to pull compost from the openings in the bottom, it's easy to slice the screen with the shovel blade.
  2. The screen corrodes over time.
  3. Rats and other rodents will take advantage of any gap between the bin and the ground.

I've been thinking about this a good bit and here's what I plan to do at some point:

  1. Pour a 'foundation' for the bin. This would be a square of concrete where in the inner dimensions are slightly smaller than the bottom of the bin such that it can rest on it. This would extend a few inches out around the bin so that it can be swept clean.
  2. Place a pretty heavy fencing material like rabbit fence across the concrete. Two layers, maybe. I might put anchors in the concrete to lock it in.
  3. If the bin has doors at the bottom, place heavy stones such that they block animals that might try to open them.
  4. Every so often (5 years?) I would remove all the compost and check the screens.

So the short answer is the screen but it might take more to really stop them. The 'foundation' need not be very deep, the point is to create a flat, tight fit to the bin bottom. Good luck.

  • 1
    Thanks for this. I thought about something similar with small concrete slabs or pavers with a hole in the middle for worms. And some mesh over. I'm thinking of letting the dog run round the back near the bin. It's obsessed with possums so I'm sure a rat would interest it – Crab Bucket Sep 30 at 21:30
  • @CrabBucket Is the dog a rat terrier by any chance? – JimmyJames Oct 1 at 14:02
  • Nope - afraid not. It's a Labradoodle. So somewhere between a Poodle, a Labrador and a teddy bear! – Crab Bucket Oct 1 at 22:11
13

30 cm is absolutely not deep enough to deter the rats. They easily dig that deep to get to food. Regular Chicken Wire is neither strong enough or is woven small enough to keep them out. Try to google "Rat Mesh", and you will find wire mesh made for keeping rats out.

Take it seriously, you do NOT want rats near your house.

10

I've had rats living in my allotment compost bins for years; we try to ignore each other. My bin is made of pallets so is hard to make rat-proof. A plastic bin should be more secure, except for the open bottom - the obvious weak point for rats to enter. I don't know if 30cm is deep enough to deter rats, they're tenacious little sods. Personally, I'd be inclined to try putting a layer or two of chicken mesh under the bin. At least that would give them something to think about. Good luck.

  • 2
    Also, put a lid on the bin. They can climb almost anything, but they don't eat steel wire mesh. (Plastic mesh is no deterrent at all.) – alephzero Sep 30 at 9:26
  • 2
    Incidentally, the best way to block up a rat hole is with weak cement mixed with plenty of crushed glass. Either they are smart enough to stop when they try to chew through it, or they come to a nasty end. Either way, the problem gets solved! – alephzero Sep 30 at 9:32
5

Depending on where you live, you might be able to attract natural things that get rid of rats.

Making proper roosting for things like owls around the compost pile will allow stalking by birds of prey. I've had limited success in the past, but it can be hard to get consistent avian predators.

The second thing you can do is encourage snakes. This can be hard to do if you live in colder climates, but in warm climates this shouldn't be too hard, especially if you live near a creek or a body of water. There's the risk of cotton mouths taking residence in your yard if you are near a body of water, however cotton mouths, while venomous, are extremely non-confrontational, to the point of absurdity at times. You can poke and prod at them with little recourse, and even when they strike they are likely to leave only dry bites, or not even puncture your skin.

Black water-snakes are typically the snake I see the most that deal with these issues. The nice thing about snakes is that if they kill of all the rats, the snakes won't just leave like a bird, so if your rats return, snakes will likely return very soon after (it can take months to get a bird to take residence in an ideal spot).

Additionally, unlike birds, if rats manage to get into your house, so will the snakes so they can't take refuge in your residence scott free.

The fact that prey will exist in your yard alone will encourage snakes. Some things you can do to further encourage their presence:

  • put up other sources of food that aren't a nuisance, like birds or bats. You google how to build both bird houses and bat houses on your residence pretty easily. Snakes will eat bird eggs and bird babies, as well as try to snap at bats.

  • provide unshaded rock/concrete/asphalt platforms for heating during the day. These materials do not insulate heat very well, allowing the snake to heat up faster from sunlight. Such basking opportunities are prime living areas for snakes.

The final thing you can do is not kill snakes. Lots of times people will kill snakes who enter their property due to fear. Simply not killing them is often all it takes for snakes to start patrolling near one's home.

Now building these residences might attract another predator: the domesticated cat. In this case, you've now got a predator that will kill for fun and doesn't depend on rats for survival. The issue with cat's are that, unless they are your cat, you aren't going to have inhouse protection, and you'll have to deal with other cat nuisance stuff (poop, rummaging through gardens, doing weird stuff, being aggressive). Getting your own cat can be ideal, but cats are also not natural predators in most countries, and can hurt native populations of wildlife in ways that natural predators wouldn't, so setting one loose just to take care of rats can pose other issues.

  • Good answer thanks. I am in Australia so snakes can be pretty dangerous here so I'm not sure if you would encourage them. If we see one that won't move on then it's a phone call to the snake catcher to move them on for us. Even the non poisonous ones you wouldn't want around. A carpet python could eat the dog for instance – Crab Bucket Oct 1 at 22:15
  • 1
    The Gopher Snake is the snake you want down in your pantry/basement. Back in the day everyone had gopher snakes chowing on the rodents. – stormy Oct 2 at 9:36
3

sounds to me like your compost isnt composting...

pile that thing up with nitrogen rich stuff (aka grass) and mix it often and no rat will want to live there.

  • 1
    I doubt this will help. Aside from any type of food (especially fats) that might be found, rodents like cooking compost heaps because they are warm. They are really unperturbed by rotting things. – JimmyJames Sep 30 at 19:57

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.