In part 1 and 2 of my compost series I talked about building a compost pile, and finding a balance in so doing. In part 3, I’ll go over what I get from it, and hopefully transcend ideas of dirt and decomposition.
Obviously, my compost heap makes soil out of all the organic scraps and bits of matter I add to it, but, like so many other things I do, there is more to it than that. Composting is natures way of recycling everything back into raw materials for use in the garden. The resulting organic matter makes up a part of soil that can’t be created in any other way. But why does it matter? It’s just dirt after all, right?
Access to dirt is what humans have fought over for millennium, and in many mythologies it is where we come from, and even return to in death. “Dirt” in the big river deltas enabled civilizations to form and humans to spread around the world. We have come a long way as a species, but we are still tied very closely to the dirt under our feet, and it is important to understand that connection.
I think most people who have gardened for any length of time know that the top 6 inches of soil is one of the busiest areas in or on a piece of land. It may not be the prettiest or most interesting, but it is the most important. Plants do send roots down further into the earth, some many feet, but the bulk of the fine, nutrient-grabbing roots stay where the action is. Deeper roots mostly do the job of anchoring the plant, drawing up moisture, and tapping into stores of heavier minerals like calcium. The top layers of healthy non-industrial soil literally crawl with life and fertility, even if all you see is dirt.
In a natural forest environment, it’s more obvious to see the importance of these top layers, and how they form. Layer after layer of leaves, pollen, dead bugs, and droppings all pile up on top of each other decomposing as they get buried. In a natural man-free setting, there isn’t any tilling, or amending going on. Soil forms, supporting all the life around it in a dynamic system of litter and growth.
I have come to my own theory about these cycles that is a simple way to envision what is going on in and out of the garden. In the same way that your compost heap needs green and brown material, the soil also has different sources for its constituent parts. Nitrogen, according to most gardening sources is a main nutrient along with phosphorus and potassium. They make up the big three nutrients that scientists decided decades ago were the major building blocks of plant health. Nitrogen and nutrition in general are tricky things, though. Nitrogen is very abundant in the air and all around us, including inside all the various creatures of the earth, but nitrogen doesn’t like to be contained. It leaks out of anything that contains it pretty quickly. In fact, it is part of daily life. Food goes bad. Bodies smell. Dyes fade. Everything jettisons Nitrogen, and very quickly.
In the garden, we amend the soil week in and week out in an attempt to keep the nutrients in soil, but it’s expensive and it usually erodes away well before the plants are done with it. Plus, nitrogen is just one part of a very complex puzzle. Despite what we have been convinced of, plant nutrition depends on a whole host of dynamic elements beyond those three numbers on the store bought bag of fertilizer. So, what’s my solution, then?
Let the bugs hold on to all the Nitrogen and nutrients they want. They will give it back when needed. Trust me! Worms, animals, bugs, and all the little creepy crawlies all are little balls of fertilizer. Animal life, strangely (or to the point, not so strangely,) is made up of exactly the things that plants need and can’t make on their own. Pretty neat how that works out, huh?
For example: In the Pacific Northwest, the major source of natural nitrogen that is available in the forests is from the salmon that run up the streams each and every year. Scientists have found through carbon testing, that as the fish move into the forest and die, their nitrogen slowly works its way into the trees through the guts of bears, birds and all the sorts of composting little creatures that live in the forest. Of course there are lots of natural nutrient cycles going on, from floods to atmospheric fixing, but the big cause of ecosystem strength in those forests and their corresponding oceans is this link between the animals, plants, and soil. I love that it is so clear, and such a ringing case for natural fertility. The salmon make the forest rich and full.
In my home and garden I often catch myself thinking about the fertility I am salvaging by composting my kitchen scraps and yard waste. It’s not a normal thought, sure, but it is a result of seeing how much growth comes from the scraps I am dealing with. Garden specialists I have talked to almost always consider compost as a brown, barren substrate. I find it odd that gardeners think this way, but it makes sense in our human world of doing things. The gardening infrastructure in this country has become so dependent on amendment industries, that gardeners only think in terms of miracle growth products and blank dirt patches. There is so much going on in a well activated garden, I find it almost funny that soil health has only recently become a hot and almost subversive topic in garden circles.
Most people have come to think that growing food has to do with those brown dirt patches adjacent to freeways all over the west. (If you are wondering why they are brown, and devoid of plants and animals, do some research about the use of bromide in agriculture. ) For me, compost is a literal and symbolic opposite to the system that kills the ground, injects it with petro-nitrogen, and manufactures green, food-like products for people to consume. Compost is about rich, dark, soil that grows, reuses, captures, and creates energy for us to use as food. Composting is about understanding our proper place on the planet.
Like my rain barrel, my compost pile is an active meditation on what it means to participate in nature. I find it is a pleasant responsibility that alleviates part of my trash-guilt, and gives me a sense of what human maturity would foster.