Making compost is easy, but you need to know one or two things to guarantee success. There are two basic methods suitable for households. One is the classical method you read about in garden books the other uses worms. Yep. BIG fat juicy ones. Both methods are explained here.
The Classical Method
Anything organic i.e. anything that was one alive will eventually break down into brown crumbly stuff that you call compost. However sometimes it takes along time and gets very smelly on the way. To speed up the process you have got to get the ingredients and conditions right.
The process needs air, water, carbon and nitrogen. The carbon and nitrogen are found in the solid organic materials you feed to the heap, and are a bit like bread and cheese: there is a optimum amount of each required to make a good sandwich. Too much bread (carbon) is dry and tasteless, too much cheese (nitrogen) is over-rich.
Most household organic wastes have too much "cheese" -rich sloppy materials like kitchen scraps and grass clippings. These do not make good compost on their own. You have to add "bread" - course, dry material like straw, cardboard or crumpled paper. These materials contribute carbon and provide air space within the mixture.
this air will eventually be used up by the decomposer organisms in the compost, and you will need to replenish it by turning the heap from time to time.
The same trick is used in some organic toilets, air is forced through the shit within a catch bucket underneath the toilet by a fan. This causes the whole lot to break down aerobically which is fast and doesn't smell rather than anaerobically which does. A broken fan should be replaced at once !
broken fan should be replaced at once !
- mix solid materials together with plenty of straw, cardboard or paper.
- Enclose in a container
- Moisten well with water or better yet urine (a watering can is useful for "exposed" heaps)
- Put a lid on top.
- Turn at least once a month, adding more liquid if necessary
So why didn't it work for you ?
Lots of people try, and fail to make good compost. The usual complaint is that it just sits there in a damp soggy smelly mess. The reason for this is quite simple, there is not enough air inside the heap for the aerobic bacteria to survive. Air exists only in the spaces between the various components in the heap. Soft materials like grass clippings and kitchen wastes quickly collapse and clog the air spaces.
Unfortunately grass clippings and kitchen waste is what most people have got! These will not make good compost unless turned very regularly, (like once a day. It is cheaper than going to the gym though).
So what do you do ?
You can improve matters by adding coarse fibrous materials which help keep an open texture and provide more air spaces. Straw is the best material of this sort, and its cheap. For serious composters it is a very good idea to buy a bale of straw and keep it by the compost heap, putting on a layer a few inches thick every time anything else is added. Another alternative is scrunched up paper or cardboard.
You will still need to turn the heap from time to time. If you don't want to do this and pay money for a gym, and all you have is kitchen scraps, grass clippings and a few weeds, the best alternative is worm composting.
Composting with Worms
If the 'classical' approach didn't work for you then its the worms for you. Worm composting is less demanding and is particularly good if most of your organic waste is rich and sloppy.
Very often you will be worm composting without knowing it, because worms tend to colonise open compost heaps anyway. If you want to do it deliberately, you can buy specially designed worm bins, but a few old tyres works just as well.
The Tyre Method
- Very cheap.
- Quick to set up.
- Flexible - expands and contracts to suit your supply of raw materials.
- Rat proof - on account of the steel bands in the tyres. You can safely compost meat scraps.
- Works in all weathers because it provides good insulation for the worms.
- Self-regulating Tyre voids provide a reservoir and a refuge for the worms if the conditions are not right in the middle.
You cannot collect the juice that comes out the bottom and which is a very useful liquid fertiliser for houseplants. (Some commercial worm bins have this facility).
It looks like a pile of old tyres.
How to do it
Collect some old tyres. They can be obtained free from garages. Choose radials, all of the same size. For a smarter appearance they should have identical thread patterns.
Stuff newspaper or used paper towels into the voids.
It is best to put the lowest tyre on firm, bare soil, but with some kind of chicken wire or old garden sieve to stop the rodents getting in.
Start with a stack of three tyres and put some finished compost, leafmould or peat in the bottom, about 15cm deep.
Put a lid on it. A dustbin lid will do, but here's a chance to improvise or make your own stylish lid which will improve the appearance of the system.
Introduce you worms. The worms you need are not garden worms but brandling worms, sometimes known as tiger worms because of their stripy appearance. They are very common and you will almost certainly find them under stones or in rotting vegetation around the garden. If in doubt you can obtain them from fishing tackle shops.
It will take a little time for your worm population to build up, so be patient at first. Once the colony has got going you'll always have plenty for yourself and enough to give away.
Feed the bin with kitchen scraps and from time to time (about once a week) add a teaspoonful of calcified seaweed, ground limestone or garden lime. This is important, because the worms need a certain amount of lime to digest their food, and they prefer the slightly alkaline conditions created by the lime.
Once the system has got going you can add all sorts of things, including weeds, grass clippings, paper towels, shredded cardboard, teabags - almost anything organic except tough woody waste.
When ready to harvest your compost, carefully remove the top two tyres and place them beside the original stack (remember the chicken wire). Place the top layers of fresh material from the old stack into the new one, and the layer of worms you will find just under the surface, together with a bit of composted material. Renew the newspaper stuffing as necessary. Leave the finished compost in the remains of the original stack to drain and weather for a few days, the use it.
This is the most effective form of lime for your worm bin. You can get it from garden centres or organic garden suppliers. Handy to have some in a rainproof container near the bin, to remind you to sprinkle some now and again. A free alternative is eggshells. When you have collected a good number, bake them in the oven and crush them as finely as you can. (A handy job for the mortar and pestle)
Refining the Worm System
If you want to collect the 'juice' you can use the bottom of a dustbin or plastic barrel as a sump. Choose the size of the bottom tyre to fit snugly, and fit a fine grill to stop the compost and worms falling through. You can then fit a tap, but then you will need to mount the whole thing higher in order to collect anything from the tap. An alternative is an angled pipe, from which liquid can be withdrawn as required by suction tube.
The Best! Use it for potting mixes, house plants, filling in seed drills. For seed compost mix with loam or sharp sand. It then goes a long way.