By Diane Kennedy.
Turning organic materials into rich soil for food production isn’t a mystery. Organic stuff is eaten by creatures of diminishing sizes, pooped out into smaller packages of nutrients, and so it continues down to the microbial level. Microbes provide the nutrition for plant roots, which adhere themselves to the microbes and extract the nutrients they need. In the natural world this process can take from days to decades or longer, depending upon the size and density of the decomposing matter. So how do we turn food scraps and goat poo and old straw hats into good soil quickly enough that we can use it? There are different styles of composting to fit your lifestyle.
The most physically demanding method of composting is the creation of hot compost. The heap should be at least 6’ x 6’ to really heat up inside. It should be layers of brown material, which would be leaves, cardboard, newspaper, straw hats, and whatever else isn’t freshly harvested, which provides the carbon. The green layers, the nitrogen, are freshly harvested materials such as mown grass, fresh poop, kitchen scraps, green leaves and plant cuttings. A good heap should be more browns than greens, should be damp enough to slightly drip when given a hard squeeze, and in our climate should probably be covered to keep in the moisture during our hot, dry months. The heap should sit for four days to allow the heating process to begin, and then turned every two days for a total of 18 days. Turning means taking the cooler material on the outside and incorporating it into the hotter inside material. The temperature of the heap should rise to between 155F and 170F; any hotter you are just burning the materials. Any cooler and weed seed and pathogens won’t be killed. At the end of this fast, hot compost, the heap should be rich soil with some stray bits still in it and almost the same size as it began.
The three-bin composting system is building a heap in any size of container, allowing it to sit and heat up, turning it into the second bin and allowing it to sit and reheat, and then turning it into the last bin for its cooling down period. This produces great compost, but it does reduce in size as it goes.
Cold compost is throwing all of your organic materials into a heap and not turning it. Over time it will rot down and there will be soil, but only a small portion in relation to what was put into the heap. Animals are attracted to cold compost, and often you will have a lot of surprise veggies growing out of it. This process is much easier on the back as you don’t have to turn the heap. However, if you throw all of your ingredients into a raised bed until it is full and top it with a couple of inches of finished compost, you can plant directly into that. By the end of a season you’ll have veggies and terrific soil.
Direct burial is taking kitchen scraps, digging a hole and burying them. Place a stone over the top if animals will dig them up. The next batch of scraps goes next to it and so on. In our warm climate, the scraps will mostly decompose in a week or so, although you’ll find egg shells and avocado pits left behind, and an increased chance of surprise volunteer vegetables. You can plant on buried scraps about a month after burying them.
Easier still is blender composting. Take a handful of your kitchen scraps, put them into your blender, fill it up with water and liquefy. Pour this watery liquid around the dripline of your fruit trees and bushes, in your vegetable bed, around your flowers, etc. It’s too liquidy to burn microbes in the soil. If there is any residue on the ground, kick some dirt over it. Do this once a month for fruit trees.
Remember that you are feeding the soil and not the plant, so avoiding factory-produced fertilizers is imperative. Also, the best soil in your yard is beneath your compost heap, so if you are planning on planting trees, start a heap in that area and when you turn it, plant where the heap had been. Building soil doesn’t have to be hard.