As someone who enjoys learning about nature and ecology, it embarrasses me to admit that I never really thought about soil when I thought about the natural world and all of its intertwining relationships. In my mind, there were plants and animals that coexisted, while soil just sat there, completely unimportant.
Boy, was I wrong. The more I learn, and the more it keeps popping up in conversations, (yes, soil keeps popping up in my conversations. Let me remind you, I am a novice gardener now!) the more I realize that soil equates life.
As the recently-released, aptly-named documentary entitled Dirt! The Movie reminded me: dirt and people are made out of the same 5 basic molecules. We are, in some strange sense, made up of dirt. We survive because the soil survives.
This documentary, which includes such big names as Wangari Maathai and Majora Carter, can fill you in on the multitudinous benefits of healthy soil–which sustains both mankind as well as the environment. I’ll let you all watch the movie for yourselves, rather than ramble on about the sheer importance, utility and diversity of soil.
The fervor of every person in the video may have gotten into the inter-dialogue of my mind…
We’ll save this all for a later date, because right now as I watch my seeds gradually grow into plants and pop above ground, the ratio of plant to soil could not be more obvious and I realize that healthy soil really matters.
The three big plant nutrients, as you may have noticed by looking at the make up of modern agriculture’s fertilizers, are nitrogen, phosphorus and potassium. This is where the commonly-used term “N-P-K farming” comes from. A rich, healthy soil will contain balanced amounts of these three important nutrients. But it will also possess several other important minerals in minute quantities. The calcium in a cabbage (that benefits our health) does not come from the plant, it comes from the soil.
This all brings me to step one in the gardening process: soil testing.
For the urban garden I’m doing this semester, we are planting in raised beds and rooftop pre-constructed boxes, so soil health was not a huge issue. We purchased soil that we knew was high quality and went from there.
But if you are gardening somewhere that has never been gardened before, especially in urban areas, it is always smart to get the soil tested so you know what you are working with.
Chemical analysis will tell you about the amounts of nitrogen, phosphorus and potassium in the soil as well as pH levels. And a slightly more expensive test will tell you if there are any heavy metals in your soil–something that really, truly matters. This is common in urban areas, where green spaces are often placed onto lots that have had previous industrial purposes.
Kits are available for doing your own soil analysis, but extension services are readily available and super cheap! This is the option I’ve always used.
Soil test information for those in the Madison area can be found here.
Knowing the results, with the help of a good gardening book, will help you to get the most out of your soil. As I slowly discover, even rich fertile soil from never-been-touched lands (if those even exist anymore) are not perfect. To find rich, well-structured, ready-to-garden soil, you often have to build it yourself.
The structure of your soil, also known as tilth, does not need to be tested. This can be self-evaluated. Good structure is important because it contains the oxygen and water required for plant growth.
Your soil will likely fall predominantly into one of three tilth categories. Humus-rich and full of organic matter. Sandy and light, feeling gritty to the touch. Or clay-like and feeling more sticky. Ideally, you want soil that possesses all of these qualities rather than one. A good test is to try and make a ball with the soil you plan to use for your garden. It should form a ball with pressure, but fall apart loosely when you open your hand. If it is too dry (cannot form a ball) or too sticky (stays in a ball after you release pressure), you can remedy this by adding compost or other forms of organic matter.
Building your on soil through compost and the use of natural fertilizers is a great way to enrich your soil and grow a beautiful garden in subpar areas. But the world of compost and fertilization are immensely complex, so that will have to be saved for another day. The F.H. King bicycle-powered compost program could fill ten blogs itself. Don’t worry. We’ll get there. It’s only April.