Now, as you may know, the majority of the topsoil on the Great Plains of North America blew away during the Dust Bowl. Here in Wisconsin, it washed away when the carpet of forest was hauled away to build great cities of the Midwest like Milwaukee and Chicago. Soils take thousands of years to develop on their own and humans, in a brief hundred years erased what mother nature had nurtured for centuries. Instead of rich, life giving humus several feet deep in places, we are now facing the very real quandary in many areas of trying to farm on clay, gravel, sand or parent rock. Five hundred million tons of sediment leave the Midwest and end up in the Gulf of Mexico each year. Much of this material used to be soil, but as we continue to “develop” as a culture, the poriton of this material that is actual soil has been reduced just because there is less of it. The percentage of parent material and toxic compounds has increased over time and therefore reduced the amount of actual soil in the mix. Nearly two tons per person, lost to the ocean from this one river. It is astounding. In my best years, with all of my lawn clippings and food scraps from my own home and a two family rental, I can nearly create two tons of soil, but just.
My goal here is to focus on some of the basic elements of a healthy compost, give the novice some encouragement and detail the life cycles that take place amongst my own piles each season. This time of year, the pile is mostly stagnant. Although it is not frozen solid, there is very little heat and biological activity to speak of, so the pile is growing slowly but steadily. As winter gets us into temperatures far below freezing, it will become a bit more difficult to find what is referred to as carbonaceous material. small branches, straw, dry leaves and stalks of many plants have already been raked and cut leaving little for adding to the pile over the next several moons.
Seven things are necessary about a 1/3, 1/3, 1/3 mix of this dry matter, (which I tend to think of as the “bones” of the pile) green fresh material, (in the urban area that I live in, mostly grass clippings) and food scraps. The exact percentage is variable, in winter the food scrap percentage goes way up and in summer it may drop to just a fraction of that “magic third”. The fourth important thing is microbes. Periodically I add a few shovels full of dirt to inoculate the piles so that colonies of soil organisms can find their way into and throughout the heaps. The tiny percentage of dirt may seem unnecessary, but for those who have tried two identical piles, one with and one without soil microbes being added the presence of them is proven essential. The other thing is air and water. Ideally, air can make it’s way through the pile, that is what the stick-like material is for. If it gets to be a solid mass, add air by turning the pile, shaking things up as it were, and adding more structure if possible. A great mentor told me that the moisture level should be that of a wrung out sponge, damp, but not dripping.
I have seen compost hot enough to send up steam. The biological activity of billions of microbes is quite amazing and the energy they create in the pile is enough to keep it “working” throughout winter. The nutrient content of the piles can be so high as to “burn” certain plants, so use it somewhat sparingly until you find the right mix that can completely degrade the materials and leave you with a finished product with few chunks, virtually no smell and that is able to absorb and retain water rather than shunting it off to the local river or it’s tributaries.
The only organic things that we do not put in the piles are banana peels, because they are often fumigated with anti fungal chemicals and meat, salt or grease. they prove detrimental to the process. Make dirt not war.