Nature mulches but humans compost. When vegetation dies or an animal defecates then the waste matter falls on top of the soil in the form of mulch. Earthworms drag the matter underground and digest it. Also beneath the soil is bacteria which digest this rotting material too. These processes turn waste into humus that enrich the soil with nutrients and allows the soil to retain water.
We achieve a similar effect with composting. This is done by piling stuff such as vegetation, kitchen waste, ash, and seaweed on to a compost heap. In so doing we are creating manure without having to pass it through an animal.
Building a Compost BinFirst you must decide where to put your compost bins. The best place is to have it as close to where the compost is going to be used. Mine are right next to my deep beds and polytunnel. They sit on the soil so there is good drainage and doesn't get water logged in heavy rainfall. There is some cover from direct sunlight from the trees nearby. You neither want the heap to be too wet nor too dry.
For my needs four bins is about right. For a small urban setup then one or two bins would be sufficient. Usually, I have two active bins. One is full and is rotting down whilst a new one is being filled. Eventually, the two bins are merged as the material rots down further. The two outer bins contain finished compost.
The photo above shows my four bins made from discarded pallets held together with bailing twine. The outer bins have compost in them, the second from the left is being turned into the bin second from the right with the pallet door in front of it.
My open bins are fine in a rural environment. For people in urban areas open bins might attract scavenging animals and result in infestations that will annoy your neighbours. There are many plastic composting bins on the market with lids to keep vermin away. For my needs a commercially made bin is too small so make sure you get the right size for the amount of material you intend composting.
I have also seen compost bins made from car tyres stacked on top of each other. Again, a little small for my needs but a cheaper alternative to manufactured compost bins for people in urban areas.
A close up of my third bin shows breathing tubes made from four-inch wide plastic water tubes drilled with three-quarter-inch holes. If a compost heap can be thought of as a cow's stomach then the tubes are its mouth and rear, allowing fresh air in and bad air out. These tubes allow the aerobic bacteria inside the heap to breath.
Almost anything organic can go into a compost bin. I have even put old fish heads in after a day's fishing at sea. It's not to be recommended though as it can attract rats. I live in the countryside so rats are everywhere but I always bury kitchen waste deep inside a heap so as not to attract vermin. A compost heap in an urban environment is a different matter so it's better not to risk attracting rats.
There is a lot written about mixing the right amount of brown and green material. It is not an exact science but generally 4 to 1 of brown to green matter is usual. This gives you the right mix of carbon and nitrogen.
For browns I use brown cardboard boxes. No matter how small the shopping list it always goes into a cardboard box from the supermarket. I am never without cardboard to go into the compost heap or to start a fire in the stove for that matter. Also, for brown material I leave some of my grass to grow and die.
My greens come from freshly cut grass, weeds and seaweed. Try and lift weeds and cut grass before they go to seed otherwise come spring you will have a nice lawn on top of your compost heap. It's happened to me in the past and I am now careful not to seed the heap.
When taking seaweed from the beach make sure that it is green. Many people wait until the storms in autumn because it rips seaweed from rocks and conveniently dumps it on the beach. By that time of year the seaweed is brown and has lost a lot of nutrients. It's far better to find a rocky beach and pluck fresh green seaweed. Your vegetable garden will love you for it. It won't love the salt though so leave it out in the rain for a few days or wash it in a rainwater bath provided by your water butt.
During the winter months your wood stove will be producing lots of ash. That too can go into the compost heap. If you have a garden shredder then shredded wood can be composted as your brown component. From the kitchen, any vegetable off-cuts, egg shells and tea bags can go on the heap.
Another ingredient I use is the famous "Number 1 Compost Initiator". It is also called Uric Acid. I'm not taking the piss, I'm giving it back with interest! Needless to say, I am the only provider. Rosie won't have anything to do with it. Besides her aim isn't so good.
Urine is good for a compost heap as it contains nitrogen, which is good for the soil. It also means fewer flushes of the toilet and less going into the septic tank. However, do not put faeces into a compost heap as they take much longer to breakdown than is usual for this kind of composting. A composting toilet is something I would like for the future and this would compost human waste over many years before it could be used on the soil.
Things I wouldn't recommend for the heap would be meat, pastry and bread. I leave it out for the birds during the morning before the rats get it at night. Nor would I put used vegetable oil in the heap. It could clog things up and it would be better used in a diesel engine converted to run on used vegetable oil.
The composting cycleIn a composting heap we attract the red worm species of earthworms. These like to live in and feed upon loose surface litter. That is why you need to turn your compost often so that it is loose enough for the red worms to perform their duties. Turning the compost also aerates the compost for aerobic bacteria.
I normally make a heap three feet high and then start filling another bin. After a number of days you will see the height of the compost heap fall. This is due to decaying matter inside the heap and the activities of the earthworms. If you push your hand a few inches into the heap you will be surprised to feel how hot it is inside there. This is the heat given off by the bacteria as they consume the organic matter.
During composting the heap will start to become compacted, which is not good for the kind of worms that inhabit your heap. They prefer lose material so it's time to turn the heap into another bin.
For turning a heap I prefer a proper manure fork. It's much easier to lift material than with an ordinary garden fork. In the photo below we can see a manure fork on the left. It has longer and thinner tines than the garden fork on the right. The manure fork has a longer handle too, which is good for the back, and can turn a compost heap in a fraction of the time it takes with a garden fork. Well worth the investment.
After a few months you are left with dark brown material such as in the photo below. Not as fine as potting compost with plenty of twigs, eggs shells and unrotted dry grass still visible but good enough for mucking and earthing up potatoes. It can also be placed on the soil for earthworms in the deep beds to drag under and feed upon. With a bit of riddling a decent enough potting compost can be created or added to fine riddled soil to create any texture of compost you require.
Feed the soil and the soil will feed your plantsWhen you put compost on your soil it is best just to place it on the surface rather than digging it in. Many people break up their soil by hand or with a machine in the belief that turning the soil does it some good. Actually, it does not. Earthworms living in the soil create burrows in which they live. There is also bacteria and fungi beneath the soil, digesting matter and giving nutrients to plant roots. When you disturb the soil you are destroying an entire subterranean ecosystem.
One aspect of permaculture is the
no-dig concept. Rather than turning the soil you simply cover weeds and grass with cardboard and place compost on top of it. The valuable soil ecosystem below is left unharmed and it's a lot kinder on an aching back too.
