compost bins or heap?

I have a reasonably large garden and produce a lot of material for composting - I reckon I could fill 3 large bins each year. I have a lot of grass cuttings which are quite slow to rot down because there's a lot of moss in my lawn - and bulky stuff from herbaceous borders which I chop up quite small. I currently have 7 very large plastic compost bins (the biggest ones you get from WRAP) a number of which are now only half full. As I live in Aberdeenshire, the compost doesn't seem to be ready as quickly as it might further south ... the material heats up a lot of the summer and the initial breakdown is quite fast but it then just sits doing (apparently) very little. Stuff that I've left for a couple of years looks exactly the same as it did after about 6 months, but I have to put it out on the flower beds as I need the bins for the next season's material and I don't want to have to buy more compost bins. I've tried adding tiger worms to the 6 month old bins (I'm guessing they wouldn't like the heat generated by the newer material) but they all just seem to disappear - there must be something they don't like in my compost?

I'm wondering if I need to be more active in managing the bins - I probably only turn them a couple of times during the summer. Or would it be better, given the bulk of material I've got to get rid of the bins altogether and pile everything up together in one heap - a sort of mini silage clamp? Or, once they've reduced in volume, could I move material into one bin so that instead of 4 half-full ones, I've got 2 full and 2 ready for new stuff? Or do I need to be doing alot more sieving and sorting? Any suggestions gratefully received - I've just filled my last bin and there's stacks more stuff that needs to be cut back and I've nowhere to put it!

Thanks!
Clare

 

Hi Claire,

another Claire here.

I have both systems, for much the same reason as you-I have loads and loads of compostible material. For me the heap works best, I don't know why, but it seems to rot down much faster. I have fixed a sheet of metal netting over the top of one of the old rubber black bins and I sieve it through that as and when I need it. A heap is better in my own opinion. It is a shame Kristen no longer contributes, he knows a great deal about this.

You do need to turn it often, but I am quite bad at this as I hate turning compost and only do it one or twice a year, so rather than be an hypocrite I would rather tell you the truth-I am bone idle and get away with it.

 

Hello Clare and welcome to the forum.
If you have a large garden where you can have the compost area out of sight I think compost heaps work much better than bins.
I always have about 3 heaps on the go.
You have to garden your compost heaps. I start with one heap and put everything on it. As it starts to rot turn it about and fork out the slower rotting stuff on to a second heap. Start a third heap for new stuff. That way you should always have some compost ready for using.
And if you can find an obliging male person to pee on the compost heap for you it's a wonderful accellerator.
Good luck.

 

Thanks for that, Alice and Claire. Do you have anything that you stack your heaps up against, or are they just free-standing?

Clare

 

Mine is free standing and covered with a on piece of carpet weighed down with bricks.

 

Are you mixing the stuff thoroughly at the start. You should mix 50:50 in proportion by volume of greens ( such as kitchen waste and lawn mowings) and browns ( dried stems , paper etc.) I wonder whether you are mixing enough green material in. Lawn mowings decompose very rapidly if mixed with browns, such as shredded paper or cardboard.

 

My compost heaps are made of wood Clare but you can use any old stuff you have or can get a hold of. Pallets would be good.
If you mix the grass clippings in with other stuff it will compost very quickly.

 

Thanks for those replies - I do mix the grass cuttings with scrunched up newspaper - inevitably there is way more grass cuttings than woodier stuff in the summer and the opposite in the autumn. The grassy part of the cuttings disappears pretty quickly - it's the mossy bits that hang around for y-e-a-r-s ....

 

The typical problem with a big garden! Is there any way you can get more browns for the summer? Lawn mowings mixed with browns makes great compost. When we used to have a rabbit the straw was great for mixing with lawn mowings and kitchen waste. We bought a paper shredder. All unwanted documents go through it and get mixed in with the lawn mowings. It is also a very satisfactory way of dealing with junk mail.
If you have too much grass dump it in a pile rather than turning the compost horrible and slimey. After a couple a years it will have turned into a black peaty like material that you can use. The excess of woody material in the autumn is a bit more tricky. Again I would not put more than the 50:50 mix cause it will spoil the composting process. I have the problem when I cut the hedges. I bought a good shredder. Some goes in with lawn mowings but surplus I have piled up and am using it on paths - like they do at some botanical gardens. Regard the compost heap not as a waste disposal system but as something that produces a very valuable resource. Home compost is much richer in nutrients than the best farm yard manure. But the ingredients need to be in the right proportions and mixed as you would a cake.

 

Hi Clare!
I have a system that uses two plastic 'dalek' worm bins and a two-section wooden sided heap.
The worm bins never get turned - I just feed them with a reasonably balanced mix of 'greens' and 'brown'. They get half emptied by shoveling the compost out of the door in the base about 2 or 3 times a year. If I'm not ready to use the compost I bag it until I need it.
The big 'heap' runs on a two year cycle. In year one it gets filled with a mix of 'greens and 'browns' and at the end of the year is turned over into the empty compartment. I plant early tatties in the second-year heap as it makes good use of the space and produces great tatties too! At the end of year two (usually in October) I empty the heap and I usually bag quite a lot of it for use in Spring.

With regard to 'browns' for mixing into the bins and the heap - I find that most of my brown stuff gets gathered at this time of year when I gather leaves and prune fruit trees and plants. This stuff I shred and bag so that I can add it bit by bit throughout the year. I've also a bin that gets used to store any cardboard that I don't want to add immediately to the worm bins.

With regard to your worms going AWOL - My guess is that they are not being fed well well enough. I think that you might be better just filling two or maybe three worm bins at a time. Each of our worms bins gets material added about every second day and the worms chomp through it at an amazing rate. What goes in at the top is ready to come out at the base easily within six months.

Another thing you might want to think about is investing in a shredder for the woddy stuff - it makes a big difference to the speed of rotting when the stuff is added to a heap.

 

Thanks for that, Dave. Lots of food for thought ... I don't really have very woody stuff - it's things like lupin, daisy and sunflower stems etc which I cut up into 3-4" pieces (depending on how much there is and how much patience I have) and this all goes in whichever bin is in action. Even in Aberdeen at this time of year, something is happening as it's generating some heat, although I guess it isn't really going to breakdown until next summer. I'm just wondering if I should store the cut stems until next spring and summer and mix in with the grass but there is a helluva lot of it and it's pretty messy-looking.

As for the worms, someone expressed surprise that I had no worms in my older compost bins so I bought a few packs and was hoping they would process the stuff that's been sat for 6 months or so, as this is what I really have a problem with - it just sits there doing nothing for such a long time, and then I give up and fork into the flower beds as a sort of partially-decomposed mulch. Maybe the worms were a bit of a red herring (?!) if what they are after is fresher stuff. Kitchen waste goes in the bins all through the year and the heat from the bins in the summer is quite high - they are generally steaming, and I can't imagine the worms would like that degree of heat?

The botanic gardens near where I work produces compost in about 9 months (even in Aberdeen!) but they have a huge quantity of garden material and turn it every week or so (using a digger) which was why I was wondering if I could make better use of the volume of material I have - ie having it all one heap, rather than split between 7 or 8 different bins.

 

Clare, I don't think the average or even slightly larger than average domestic garden can produce enough waste plant material to maintain a high enough cooking temperature. You really need a pretty big and regularly fed heap for that to work.
As for your worms getting cooked, I don't think there is much chance of that as if they start feeling the heat they'll dive down into the cooler parts of the bins until things cool off a bit. When I have grass (or moss!) to compost I try to divide it between the bins and the heap, and even if I split it between them I always get quite a bit of heat during the first week to ten days.
Thinking about your thicker stems - worms will have a problem with them until they start to break down, though if you had a 'heap' on a two year cycle they'd almost certainly rot down. The other alternatives are to invest in a shredder and feed to the worms (and/or heap) or to dry the stems and incinerate and use the ash as a phosphate feed in spring. Don't use ash in winter when plants are dormant as what it puts into the soil gets leached out before the plants are ready to take it up.

 

I would agree with the above with regard to a shredder. It breaks the material up and produces more surfaces on which fungi can work. With a compost heap there are two stages to it and the compost heap being cold does not mean it is not decomposing.
When a heap is first made the bacteria get to work and they use the soft nitrogenous material and they produce heat - that is why lawn mowings heat up quickly. If they were on their own they would use up all the air and die too early leaving a horrible sloppy mess. Eventually they do die out as they have done their work. However the fibrous material is still intact. Next fungi move in and they eat away at the fibrous material and that takes time. That is cold composting, which is what garden composting is.
To hot compost you need a big heap and it needs to be turned every few days to get air in and you would need a tractor to work on the scale that they do.
You can help things on your heap by pushing air in, perhaps by forking, or poking a stick in. they do sell a device that you stick in to produce air holes.

 

Thanks Dave and Geoff
I had one of those aerators but I broke it - perhaps I had a bit too much heavy stuff in the compost bin!

 

So its not as tough as they try to make out!
I think I will save my money and keep with whatever stick comes to hand.