In the modern world, our custom is to think of working to make money to buy goods from a store, and then to throw the goods away when we are done. That has been our custom for only a matter of decades, and already the largest structure created humankind are rubbish dumps. Before the invention of things like plastics and throwaway goods, however, there were no rubbish dumps, for when we used natural materials, there was virtually no waste.
Waste does not exist in nature; everything is part of the same bio-mass, and while some micro-organisms help turn soil into food, others help us digest the food, others break down our waste and turn the manure, dead plant matter, wood or other natural materials back to soil again. You will have armies of billions working for you, and while they do not complain or need to be paid, they will need food, water and air.
Soil packed with germs that mine valuable materials from the soil and make them into useable form for plants – certain kinds of actinobacteria, for example, “fix” nitrogen, which is all around us in the air but not in useable form, and puts into the soil in a way plants can use. Other germs fight disease, store water, or aerate the soil – and they make more of themselves.
When you compost, you are simply encouraging some germs to thrive and discouraging others.
All natural materials have a certain ratios of carbon and nitrogen – those with a ratio under 30, or 30 parts carbon to one part nitrogen – are called greens, and they will compost more quickly, and will form the bulk of your compost. They can include all kinds of kitchen waste – but no cooked food, as it will attract vermin. Feed those to your chickens if you have them, or chop up your bread and feed it to the birds, but don’t put it in the compost. You can also include lawn clippings, although remember that you might get weed seeds in the mix that can germinate in your garden later.
Browns are waste that is largely carbon – straw, paper, cardboard, or in our case the sawdust and mulch from inside the chicken coop – and should be composted separately and given more time. Since it’s mostly carbon, some of the other ingredients would help balance out the mix – urine is a great thing to add in whatever way does not violate local ordinances. Kitchen waste should be left at least a year, brown waste often for two years, depending on factors like the size of the parts and how damp they get.
Germs have to breathe just like we do, and different germs inhale and exhale different things. Fungi and actinobacteria breathe oxygen as we do, and you want them working your compost, so you need to turn it every month or so to give them fresh air. If the oxygen in all the little soil pockets has been used up, the anaerobic (oxygen-hating) methanogen bacteria step in, and while they too will break down the materials, you probably won’t like the smell they generate.
You don’t need to buy a special bin to compost – some people just pile it up in a corner of the yard, but for the sake of tidiness we nailed together planks of wood into a cube about a metre and a half on each side. Rather than nailing the planks on one side, we left them in slots so the entire side could be removed a bit at a time and the compost added, removed or turned. We just emptied the compost bin that we had been using for the last two years, and almost everything in it had turned to black earth again, ready to go for another year and start the cycle again.
-- Written for the Kildare Nationalist last week. Most of you know this already.