I did a little research on our soil types here in Northern Indiana last week. I wanted to find current information on two soil amendments: marl and agricultural lime. Marl is defined as an “earthy deposit of clay and calcium carbonate used as a fertilizer for soils deficient in lime”. As a kid growing up on our family farm in Bristol, IN, I can remember my dad having a local company come to spread lime on our pastures. Lime is used to modify the pH of your soil (the balance between acidity and alkalinity). The pH of a soil can affect a plant’s ability to take up nutrients as well as being a factor in the quantity and diversity of soil organisms. The question I was asking myself was not about correcting pH, but rather, if I needed to correct my pH, where would the source of lime come from? This same question can be asked for all “organic” soil amendments. If sustainability is a goal, then the sourcing of inputs is part of any balanced equation. If what goes on my fields came from any distance, then two “sustainability” problems arise. The transportation costs (costs being dollar amount as well as environmental cost) and the depletion of that input from its original location; removed, trucked or by train, and put onto my fields.
Marl is an input that can be found in certain ponds in Northern Indiana. The county extension agent in Elkhart County knew of two such ponds in our county alone. The dredging of marl from ponds for spreading on fields is not commonplace anymore. Agricultural lime is the preferred input. It is, essentially, crushed limestone which has been quarried. The agricultural lime used in Northern Indiana is primarily from the southern part of our state. Obviously, the extraction, processing, and transport of this product is relatively expensive. Marl, on the other hand, although a more local input, is equally expensive to remove and transport. Either option poses the question: is liming one’s fields a long-term, sustainable option?
The above example is not meant to suppose the abolishment of any such practice which involves amending your fields or beds. I am no schooled expert in soil science or agriculture for that matter. For me, it is a matter of personal scale and personal experience. My farm is small by any comparison; less than 1 acre of actual production. What is true for me is that I can no longer afford trucked-in inputs and at the same time achieve my goal of being profitable and environmentally sustainable. Growing my soil is the cornerstone of my whole operation. Without a reasonable method to build and maintain fertility in my fields, my little farm can’t be sustained. Trucked in inputs, whether amendments like green sand and lime, or organic fertilizers, kelp, and fish products and even soil mixes for my transplants; all of these are becoming less and less reasonable options. I could charge more and maintain my current practices, but that would only be addressing the financial considerations and not necessarily addressing the problem of soil health and future fertility.
My evolving theory is this: Given the area I live and farm in, I may need absolutely zero trucked in inputs of any kind, including local inputs like marl or municipal mulch. Defining local is key. My “theory” would have to define local as what is available on my farm (or could become available given time). Of course this is not really “my” theory at all. It is the basis for permaculture and bio-intensive farming, both of which are rooted in very old agricultural systems. Northern Indiana has very good soils to begin with. Having over-looked this initially, I was quickly lured into the marketing madness of “organic” quick fixinputs, products, and tinctures. I am talking about 20 years ago. Today, the “organic” product list has quadrupled and then some. In the past few years, I have decided that true sufficiency farming can be accomplished. Some posit the whole idea as current fact, but I have not experienced nor seen it yet. For me it is still theory, albeit a darn good one. Testing of this hypothesis is where my farm is currently. Some things like compost cropping have worked beautifully, others, like raising comfrey for compost tea are still being explored. The cold fact is that moving in this direction, away from outside inputs, is going to take time. I am okay with that because I have given myself no other choice.
When I started farming, growing an abundance of food to sell was my primary concern. Soil health, I figured was a given as long as I used only “good” organic products and never “bad” conventional products. That was a foolish position. I realize now there is no “magic-bullet” organic product or single specific method to sustainable, healthy food production. What counts is happy dirt.
My first encounter with the idea of zero outside inputs (or at least extremely minimal) came a number of years ago. I was looking at all the soil-test data I had collected for an upcoming organic certification inspection (OCIA). I had a pile of sheets with specific data on the pH and major and micro nutrient makeup for each field. The soil tests also included recommended soil amendments to correct any deficiencies. Needless to say I was a bit overwhelmed. I managed to put together a plan on paper for purchasing all that would be needed to “fix” my dirt. A short time later I was reading about pH in J. I. Rodale’s How To Grow Vegetables And Fruits By The Organic Method. There it stated “The nice thing about using organic matter is that a lot of it can be used. And it doesn’t hurt the soil. It acts in a manner to control either excess alkalinity or excess acidity. Whichever way the soil is bad, either too acid or too alkaline, organic matter will tend to correct it.” I pitched my soil amendment plan and began to focus on intensive compost building.
I am not advocating against the “total” use of outside organic inputs. For sure the sourcing of local resources like animal manures and municipal compost have a role to play in local sustainability, but it would make sense to me that those inputs would be used in close proximity to where they originated. City compost for urban gardens and animal manures to fertilize on-farm pastures, that in turn feed those same animals. I still use Fertrell organic fertilizer, but less and less each season. I still amend my heavy clay areas with greensand, but the goal is to replace the greensand with intensive buckwheat cover-cropping and incorporate finished compost into those areas when I can spare it. Little by little, I hope to reduce any dependence on outside inputs and replace them with my own home-grown plant based fertilizers. I have a number of leaf piles breaking down into leaf-mold which will eventually replace the peat in my potting mix. Home grown potting soil would be a great help, but it sounds a lot easier to accomplish than it is. Especially if you need 100 cubic foot per season. Possibly a local source of high quality, balanced potting soil in my county would make more sense than trying to produce it all on farm.
Any way you dice it, to grow soil requires a healthy farm to begin with. And a healthy farm should be a reflection of a healthy locality, including other neighboring farms and municipalities. Shipping in much of anything for farming in Northern Indiana does not seem to make much sense given the environmental blessings of our immediate region. We have good diversity of soils ranging from sand to gravel to loam and clays. One hears the term “nutrient dense foods” a lot today and I can assure you, “nutrient dense foods” are a byproduct of “mineral rich” soils, which we have a bounty of here in our area. We have a fairly robust watershed if we can just keep it clean. All the swamps and swampy-swales in our region help to filter and recharge our aquifer. If only our land developers could respect that wet lands are crucial to our abundant, relatively clean water supplies. Our region also is blessed with good overall drainage. Last year’s extra rainy start to spring did not cripple our local agriculture as much as it did in other parts of the Midwest. In addition to wetlands we also still have a lot of woodlands, although we could always use more. Northern Indiana is pretty green in the spring and summer. All this is in respect to our side of the Indiana-Michigan state line. I could continue for some length just talking about the abundances our neighbors to the north have at their disposal.
In a nutshell, Michiana has the “fat stack” when it comes to natural resources. We probably have very little need to import anything for our farms, our gardens, and flower boxes. The only thing we need to import is new young farmers, or at the least, we should cultivate the ones we have here already.