Rat proof food waste composting

A bit of background- I hang out at an off-grid community which unfortunately has a major rat problem. I'm currently looking at solutions for food waste disposal (mostly vegetarian/vegan) that keeps waste decisively away from the rats. What has shown some promise is an in-vessel system based on a 205 litre barrel. I use guttering and 100mm waste water pipe to create ventilation channels down the cooler outside and up the warmer centre to maintain air circulation, and I've had a fairly quick burst of heat and volume reduction down to about 60% within a few days- how can I build on this? The resources on site include:

Tree surgeon woodchips, cardboard, sawdust, and straw.
Charcoal- lots of it.
Aqueous urea solution.
Reclaimed wood for rat-proof lids.
A trommel, currently with a 10mm screen, but that can be easily adapted.

My questions- which may seem naive- I'm approaching this from a waste management and process technology background, rather than a gardening background, would be:

What defines "good" compost?
What timescales do I need to think of to make "good" compost? To just get it to a point where the rats won't be interested, and it can be buried to let the earthworms do the rest? I'm hoping that simply trommeling out the finer particles is the answer.
What creatures should I let in/keep out? Remember, the general idea is to keep things out unless I want them. Are fruit flies to be welcomed or suppressed?
What sort of things will grow well in the resulting compost?

Thanks for any replies.

Vegetarian implies some eggs might be eaten? Can the scraps be fed to chickens?

http://geofflawton.com/videos/chicken-tractor-steroids/

http://geofflawton.com/videos/grow-chickens-without-buying-grain-feeding-compost/

https://permies.com/t/55362/chickens/critters/Chickens-compost

I agree with Tyler. Especially since you seem to be dealing with food waste in volume. Processing it through chickens first will be an ideal way to reduce the bulk, decrease the interest of rats (unless the chickens are small!), and obtain an additional yield. Another possibility is black soldier flies, though they need warmth and would only really work in the summer. They will even break down chicken manure and cycle back a feed yield for chickens that way (or fish, or wild birds, or whatever.....)

Thanks for the replies. There are two chickens on site, but I would, at this stage, be reluctant to push forward in this direction, due mainly to the input needed to ensure the chickens' welfare and quality of life. Is there potential in the liquid effluent which could be sucked from the bottom of the barrel, and used as an innoculant for biochar?

"Good compost" comes from the widest range of ingredients you can find, fruits, vegetables, mowed grasses, weeds, manure. Slow compost tends to be better than fast as it contains more microorganisms such as bacteria and fungi. These are what roots are looking for.

If rats are the main problem, you really need to get rid of them because they can harbor disease for humans and animals, get into car engines, or at least keep them minimized.

I like worm towers that are large PVC pipes or plastic pots drilled with holes and sunk into the ground. A heavy lid will keep out rodents. The bottom half of a 2 foot tower is drilled with holes big enough to let worms in. Layers of fresh kitchen scraps and manure are put directly into the buried towers and the worms come and go. They shouldn't contain onions or citrus peels. Put them about 10 feet apart and worms will come to them, you probably won't need to buy any worms.

http://gardendrum.com/2013/01/12/how-to-make-a-worm-tower/

http://www.redwormcomposting.com/gardening/worm-towers-2013/


everything grows well in compost. that's how Nature does it. Leaves drop off trees, wild animals like rabbits poop all over, the worms come up, and that's what we're trying to mimic.

As far as keeping things in and out, definitely rats because they chew plants to make nests, and they eat vegetables and fruit, along with all their other rodent friends. To avoid an overabundance of insects, collect all fallen fruit, don't let vegetables rot in place, bury it deeply, like a hugel trench so the worms will find it, too. If you have greater amounts than a worm tower can handle, hugel trenches are very good, and stay damp so the worms will come and stay.

Worms are your best tillers and fertilizers, so feed your worms that feed your soil.

One other thing about what critters to keep in and out, wild birds will come and dig for bugs, which is very good. But they won't come if cats or dogs are in the garden. I've seen flocks of at least 50 songbirds come and spend time on my fenced 1 acre.

Snails are a problem, and raccoons will climb fruit trees, breaking branches, to get to the snails.

Large predatory birds are great at going for snails, like crows and ravens, but they will also dig in an open compost pile and eat fruit. I cover fruit trees that have fruit on them with sheer curtains that flap in the wind and scare the birds, and are less dangerous to animals than plastic netting. Plastic netting is really bad for birds and bats and good snakes that get caught in it. I have had way too much trouble with netting. But the sheer curtains allow light in and do a good job.

Tyler Ludens wrote:Vegetarian implies some eggs might be eaten? Can the scraps be fed to chickens?

Just so you are aware, EU law prohibits the use of kitchen scraps for chicken feed. I was first made aware of this in a newsletter from the British Hen Welfare Trust, a charity I support.

Thanks for the additional replies- @Galadriel & Tyler- going down the chicken route can't happen as it would jeopardise funding from a vegan charity pot, and there are concerns that there isn't the critical mass of know-how to take proper care of the existing two pet chickens. I do like the idea of the worm towers, and they should be easy to implement with clippy top plastic barrels.

We used to joke that we had the healthiest, organic rats around when we did open compost. I'm sure their coats gleaned ;P

Have you thought about using an old fridge?
Degas and lie it on its back. Drill a drainage hole, place a bucket underneath for your compost tea. Drill some air holes in door, to allow air in but critters out.

We use these as large community worm farms, and they will compost your vegie scraps more cleanly than an open compost, while also keeping out pests.
Good luck!

Hi brian,

Seattle sells "Green Cones" for urban composting, specifically because they're rat-resistant. This link (warning, PDF) has information on why to use it, and how to make it even more rat-resistant: http://architecture2030.org/files/GreenBuildings.pdf

They're pricier than just a simple box, and you might have more daily waste than just one can handle, but they're quite a nice system.