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2 years ago I built this composter, similar design and size etc to one I made at a previous house.
Problem is this one doesn't really work! Some stuff turns to mush in the bottom, but there is no heat, or any signs of worms etc, has more of the feel of a stagnant pond. I've used it on the veggie patch last winter and now have random strawberry / tomatoe plants growing so obviously stuff hadnt decomposed. The last one had an incredible amount of heat and stink, but worked in 1 season.
Any ideas how to get it working?


Pee on it?
Too much green, it may need a bit more tougher stuff. Grass clippings alone isn't ideal. Some people say shredded cardboard is good, mine gets handfuls of whole weeds (eg nettles, ragwort...) and the annual cut off the meadow etc. plus the kitchen waste is usually in paper bags.
If its mushy it sounds like too much green/nitrogen, and not enough brown/ carbon. Try adding more twiggy stuff or cardboard, and mix it in a bit better maybe. Pee is a good activator.
To be fair I guess at the old house we did put cardboard in and havent here. Small branch cuttings etc too then?
Yes I probably do need to turn more often too. Will try pee !
brown/ carbon
Are decomposing leaves class as brown?
Edit - looked myslelf. Brown
At our old house we had no paper recyling so alot of it went in the composter, here just chuck in the recycling.. must be part of the big difference
Drill more vent holes? Looks a bit to enclosed to me, but the wife is the gardener is our house not me.
My knowledge is purely based on sitting through episodes of Beechgrove Garden! 🙂
Too much grass cuttings IMO. It doesn't break down very well if there's too much.
I'd try to get more of a mixture of stuff and get rid of grass cuttings another way where you can.
How often do you turn it? Regular turning is the best way to get it cooking. To get it going initially, I would turn it once per week for say 3 or 4 weeks. Once it's got some heat in you turn it less often.
The right amount of moisture is also important, which basically means keep it damp. If it's not thoroughly moist then water it.
I wouldn't fuss too much about green/brown (I never have), if you keep it moist and keep turning it then it will get going.
You are getting anaerobic conditions, you need more aeration, bulking with drier material (twigs/leaves/shredded cardboard or regular turning. But it looks like it's mostly grass cuttings in there which is always going to be difficult to get going well.
All the above.
We put in a layer of torn up cardboard at least every time grass clippings or other green stuff goes on.
We collect all the twiggy prunings, save them up then I bought a little shredder to chip them up, on they go as per cardboard
Definitely pee on it. Also no need for the lid ime, let the rain in
All tea leaves, veg peelings, egg shells etc go in.
Ours never gets full, it composts down quick so there is always space
I don't think it's a ventilation problem as our plastic bin has no vents and is full of critters and thriving.
We don't put grass in ours due to being lawnless and no cardboard, so it could be too many grass cuttings.
Our old wooden bin also used to be the cats favourite sleeping place, until the local car experts were being chased by the police and crashed through the fence, the compost bin absorbed the shock and probably save the scrotes from serious injury. Luckily the cat was else where at the time.
Its missing 20 slow worms and a snake.
Maybe add some straw, only a couple of quid from local horsey place, get your grass layered with straw. Turn regularly, wee in a pot and throw that on. Add kitchen waste, peelings, egg shells etc. Give it a month or so you ll have really good compost.
more brown stuff and more liquid - not just pee, but also water and cuttings with lots of water eg dahlias.
We’re fairly careful with the mix of green and non-green, also too wet/too dry as others have mentioned. And it’s been doing ok a few years. But I chucked a capful of this stuff in this year and it’s going like the clappers now! Other brands are available.
If too wet, my mother in law swears by chucking some corrugated card in. Easier to find than straw for many.
It really needs to be somewhere in the garden where two sides or edges meet. I saw a documentary about this one Saturday morning in the late 70s or early 80s, its never left me.
Its missing 20 slow worms and a snake
I love the way this place makes no sense unless you read all the threads.
I put a load of grass in ours but I feed it plenty of green waste and coffee grinds too. Also gets plenty of apples off the tree (good for the occasional crumble but not much else!)
My dad has a concrete block compost pile, insulated his with celotex. Mostly grass goes in as he has large lawns. It gets very hot, and is like a turbo compost pile. It has a sealed lid so no air getting in. Maybe not too many worms in there but the microbe action must be off the scale!
I love the way this place makes no sense unless you read all the threads.
If you don't read all the threads you don't deserve understanding.
Like others have said, you need more brown/dry material, but the difference might also be to do with the position. I have a hotbin (fancy hot rot compost bin) which is insulated, but even then the sun falling on it makes a massive difference to how hot it gets. More heat = faster composting.
Too many grass clippings doesn't do much good for ours. Keeping it wet is important and regular turning. I'm reliably informed by our local composting expert (80 year old woman in the local green party, absolute legend) that if you put cardboard in, then wet it first, and don't put too much in.
Also, in terms of stuff growing in it, I was always told not to put stuff with seeds (ie tomatoes) in there?
Where is it? We moved ours from a north facing in at the side of the house where it got no sun even in summer to a south facing sunny location and its now composts instead of preserving like a peat bog.
One thing I do which seems to help get more in, mix it well and get it started, is use my mower to chip the twiggy stuff. For example when I prune a bush anything small enough that I cut it with the secateurs is spread out across the lawn and mowed. This chips it small and mixes in some grass cuttings so, although still a bit woody, it's not far off a decent mix for composting.
My experiences -
I used to have big contained heaps with carpet to insulate, this generated a lot of heat but also the rats loved to live in them. I now use the plastic Dalek type bins that the council used to sell. These are positioned on concrete where they get a lot of sun, I use a 60/40 green/brown mix where the brown is often torn up cardboard. I do mix some grass clippings in as it’s a good activator (but not in thick layers), I use urine to wet and also stir and mix with a fork about once a week. The heat generated is tremendous, I leave some old compost in the bottom to start the new bin off with bacteria, worms etc. Being on concrete and without any doors on the bottom rodent incursions don’t happen anymore, there are also no air holes in the bins. Compost is produced in a couple of months. I did make some educational videos during lockdown but my sister thought I was going mad!