Building a new composter under a tree

We used to have a composting area under a couple of big trees back on the farm where I grew up. It wasn't a bin as such, but all waste went on that pile. I seem to remember my mother watering the pile, and now I realise it was because the trees kept it too dry, I suppose! I can't imagine it would do your tree any harm, quite the contrary

Only other thing I can think of is that you want your composter to get some sunlight to warm it up - probably not a problem unless the tree canopy is very dense.

My composting area is under trees, it doesn't get as much light or moisture as it could do but it makes compost. I have 3 daleks at various stages, have just been emptying one earlier today as it happens.

As mentioned above...water and light limitations...but it'll still work but slower than it could be.

Every bit of freebie/organic compost is like gold dust ...aka black gold

The only part of your plan I would question is the pest repellent bit - that really also depends on the things you put in to compost - I compost kitchen waste in mine and I've found the simplest way to make sure rats dion't get into it, was to make a composter out of a plastic barrel on a metal frame.

I agree the points made above and would add "middle aged spread". The wire is likely to "bulge" as time goes by, unless you add some support half way up. I did the same for leaf mould and after a year the whole lot drooped. It will be worse with compost.

An old allotment neighbour use to dry off all the weeds and bury them in a pit (not too deep) along with any other rubbish he brought in. Always seemed to work for him.

\bill

I'd also suggest a tarpaulin to cover it - stops it getting too wet in the rains and hold some moisture in during the drier days.

Are you aiming for hot compost or cold compost? If it's hot compost your after make sure it's going to be easy to get into to turn - possible build two connecting (saves one wall ) with the fronts of each open-able. Hot compost won't be bothered by shade as lonf as you keep it moist and aerated - google Berkley Compost Method. I'm not using that method, I'm turning mine once a week adding new material to the centre before I turn the old onto it so that it gets up to heat and starts breaking down quicker - of course I'll have a cut off point for adding new stuff so that it finishes off in time to use.

If it's cold you can use a compost turner tool just to get some air into the centre to stop it going slimy and smelly, prodding it in when you pass.

Taking into consideration all of your comments :

This design is based on 1.5metre stakes and 1.2metre wire aviary mesh (this is much stronger than chicken wire which is less rigid). This design is for 3 compartments, all 1m2.

I cannot see the point in lining the base with aviary netting if the netting on the outside perimeter is deep enough in the ground. The only issue is if rats are clever enough to burrow underneath the netting and get into the heap. Lining the base of the trench with wire netting may be an option.

The reason I am going a little deeper is because I have read up on the Berkley Compost Method and apparently this requires a 1.5metre deep heap (see attached photo). Although most of the compost I will be making will likely be cold I would like the option of hot composting, and so will design this into the construction.

Over-shading is not really an issue here as the tree is not big enough to cause it. I was more concerned about the trees roots being affected by biological activity.

Things I still need clearing up :

I'm not exactly sure how to line the base of the trench without it being frustratingly in the way when I go to turn the heap.

I'm not sure how the front section of mesh will be fitted to the stakes to allow for it's easy removal. It could be bent/pushed so 200mm would be left in the ground to the depth of the trench, while the rest is stood on. This may provide an easier route for rodents to get in and under if I am not careful.

I'm not sure about the roof construction. It tarp is used it is unlikely to pull tightly enough to stop rats from climbing up the mesh underneath the tarp and getting in. Wire mesh roof with trap door seems plausible, but is more fiddly and difficult to remove.

The stakes I am planning on purchasing come in both square and round profile. I may use round as they are generally thicker. I would anticipate that at least 50mm diameter will be required, otherwise there may be risk of snapping getting them into the ground.

Why am I not using timber

Cost. This is a lot of timber if you factor in all the timber required and it needing to be rodent proof. It's also more cumbersome and difficult to build.

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Feedback welcome

The tree root are unlikely to be affected by the compost pile - what happens to all the leaves naturally when they fall? They make their own compost piles under the tree. Any nutrients seeping out the base of the pile will just feed the tree.

Looks like the one of images you attached has a roof design you could adapt to the square shapes. I just pull a tarpaulin over the top of mine and weight it down planks.

I made a temporary compost pile last winter using a circle made out of the square mesh (5 foot diameter, 3 foot high) - sturdier than chicken wire and stood up by itself, just wrapped onto itself and stood on the ground. Didn't use supports as once the bin was full the circular shape supported itself. Again just a tarp for a cover. Had far too many branches in though so it's gone into the hot pile this year where it's breaking down nicely, although the bottom of the pile had good compost it was still full of twigs and sticks. This year it's shred shred shred.

I don't worry about rats in mine - if you keep disturbing the compost (either by turning it or by prodding and poking with a compost tool) they'll not set up shop.

My new setup this year consists of three "U" shaped bins 5x4


One is for manure, one for compost and 1 for turning into. I'm not doing it every 2 days - I don't have the time or energy to do that and there's a lot of stuff to turn. I turn it once a week and I'm resolved to the fact that I'll lose more volume that way.

Cost so far

Based on the stake and mesh design as per the picture : 8x timber verticals, 2x scaffold poles (already there), 14metres of wire mesh.

15metre roll of mesh = £26.99
Pack of 10 fencing stakes = £25
This leaves 2 stakes and 1 meter of mesh unused.

There is a lot of preparation for this design. A lot of digging out. There's also a question of how long the stakes will last before failing. I do see them having a life of no more than 12 months. A lot of fiddling with the mesh, and unfortunately the best I can find online is 1'' x 1'' which will likely let mice in, and some small rats. This might mean I have to add another layer of a cheaper mesh like chicken wire to counteract the oversized holes.

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Is that steel corrugated roofing? I do wonder if it may work out cheaper to use that instead of stakes and mesh. I can't see rats gnawing through that stuff. How easy is it to bend ? Do you know what sizes it came in originally ?

I'm going to have to finalise something soon because it needs to get done

I made mine out of pallets, I put a really heavyweight one (blue) on the bottom and stapled fine wire mesh to it. Then I fixed three more pallets (also with mesh stapled to the inner sides) vertically on the back and sides. Then I pulled the slats off a few more pallets and used these to 'stack' up the front as the compost level inside rose over time. I chucked another pallet on top which I intended to cover with roofing felt, but I never got round to it...
I made two like this side by side, cost me practically nothing, just a roll of wire mesh and some L shaped fixings. One thing i messed up though, was setting them well on the ground - as one filled and got extremely heavy, it started to lean (my plot is on a slight incline). Keep meaning to empty it and sort it out, but i haven't found the time.

I was lucky as the metal sheeting was on the plot when I got it and I managed to resist all efforts by other plot holders to take them off my hands. Each bin is made up of two arches of the corrugated iron (tied together with nylon rope). There were 4 making up a large fire pit and 2 more making some sort of shelter. The 2 back panels that were on the shelter were cut off and are used at the front to close off the 2 filled bays.

I've a few lengths of flat sheeting as well - I don't think it would be easy to bend without proper jigs. If I used them for a bin I'd have to use posts in the corners to bold to.

I have some 1/2 " square 3" aviary mesh that was also on the plot used as a dividing fence and pen/cage for fowl by a previous owner.

Hi guys, so I considered pallets for a long time, my existing composter is made from pallets. The trouble is that there is no protection from vermin, the heap is not turned frequently enough to heat up (and so weeds stay alive), and vermin come and go as they please.

After thinking about this quite a lot (much more than I probably should have ) I've decided to go for a plastic one. Here : https://www.amazon.co.uk/4smile-Comp...ic+compost+bin

Reviews are good. The supplier states that the plastic is stable. I'm going to try and improve it's life somewhat by fitting this inside the existing composter after I've removed what compost there is, and covering it somewhat to stop the the sun hitting it directly.

I honestly think this is the best option all considered. The weeds will break down/die within the bin as light is eliminated. The pile will break down quicker as material will be more concentrated in an enclosed and moist space (it's bound to be hotter). Vermin will be almost completely eliminated - especially if I sit the bin on some wire mesh, a it's more cost effective.

Please feel welcome to crititise this approach if you feel the need? I think think that by building a new composter elsewhere I'm just moving the problem somewhere else. It will have the same problems this one has, but there will be 3 instead of 1. It will be nice to have a lid to open and empty the fruit and veg waste without attracting a bunch of bluebottles and fruit flies.

p.s. I'm still open to being persuaded.

I'm trying not to sound critical as I'm just relating my experience, and everyone else has had different experiences.

I have 3 very similar, although not exactly the same.

• One has just been emptied and incorporated into the new big bin as it wasn't breaking down.
• One will be emptied and incorporated into the new bin as although it's broken down a bit more , it's breaking down slowly. The ants are helping break it down.
• One is in bits and is currently being used as mulch.

I found that they don't have the volume to keep the compost hot. Although they're black the sun doesn't keep the compost in the middle warm.

Turning them was a pain, I do have a compost turning tool but getting it all mixed up is hard, especially near the corners. I found that it was difficult to keep the moisture levels right and they often dry out - watering them often only reached the top few inches before the water found the easy path down the sides avoiding the centre.. Getting finished compost out the hatch isn't easy.

I have the same problems with the dalek. They're fine for making cold compost and letting things sit in them for a couple of years but I wanted to be able to make hot compost and these didn't cut the mustard.


Your pallet compost bin sounds like my plot neighbours - where he just throws stuff in and hopes. I don't know when he last dug into it to get compost out, when I asked he couldn't remember.

I haven't had problems with rats in the compost despite my bins not having bases/mesh bottoms - I would stir them the best I could without pulling the bin off and spreading the compost around the place (the best method for emptying them) and poke them with an iron rod to let air in.

The kitchen scraps, bokashi, garden waste, weeds, prunings etc never made a massive amount of material so the 3 daleks and 3 cubes were loaded up one by one and allowed to break down - I had them sitting on beds so that the run off could be absorbed by the crop in the bed. It sort of worked but never produced enough compost.

Last year I started getting the jobbing gardener round where I live to drop off his garden waste and lawn clipping and I now have a lot more materials to compost.

After 5 years of using the plastic bins I decided to build something better and I was going to look for pallets but used the arches in stead - I don't have that much left to burn and now have a new, smaller fire pit made out of a wheel and washing machine drum.

Originally I had one bin which I piled everything up during the year - needless to say it wasn't doing too well. By 8th August I had 2 more bins (one full of manure) so was able to turn this pile properly adding new material to it - it got hot

By the 19th it was down to a steady 35 degrees and I had a delivery of several bags of grass cuttings so I emptied a dalek and one of the square bins, incorporated the grass cuttings and made these the centre of the pile that I turned the old pile on top of. The pile had gone a lot further in the last 10 days than it had the rest of the year. It got hot again

Today I turned the pile again onto a smaller pile I made yesterday with grass cutting, garden waste and the contents of another dalek (more broken down but cold composted so still risk of weed seeds). The stuff I had added 10 days ago wasn't as immediately identifiable and the rest is breaking down nicely. There's alot of twiggy woody bits in it - lazyness on my part as I didn't bother taking them home to shred them - I'm paying for it now as they knit together making turning it a bit harder work. I'll remember that this autumn.

In between turns I jab a tree stake into it several times to let air get back in.

Work schedules and the fact that I'm not going to put that amount of effort into it means that I'll not be doing the full Berkley and turning it every 2 days but a turning every week or two and jabbing at other times I think is going to work. Getting it hot is my main aim to kill off weeds and pathogens.

As it's hot or being turned (or being jabbed) I don't think the rats will look at it as a desirable abode.