(Continued from Part 1.)
Principle #1: You Are a Microbe Farmer
Do you want to sustainably grow healthy, nutritious, produce? Congratulations . You are now a microbe farmer! The first principle of biodynamic gardening is you are no longer growing plants, you are raising trillions upon trillions of microbes. If you can create an environment that supports a healthy soil ecosystem full of bacteria, fungi, and other soil organisms then ANY plants adapted to that environment will thrive.
The Bionutrient Food Association (BFA) spent 3 years surveying nutrient quality across 21 crops. They compared the soil samples with the crops that were produced in those soils, and also surveyed the growers on the techniques they used. The difference in nutrient value between the best grape and the worst grape was a factor of 15! You would have to eat 15 of the worst grapes to equal the nutrient content of just 1 of the best grapes. The only factor the BFA found that significantly correlated to the nutrient density in the food was the level of microbial life in the soil. It didn’t matter if it was an organic no till operation vs a conventional pesticide spraying operation. If the soil was alive, the crops were denser in nutrients and higher in quality and flavor. In other words, if you can make sure the soil life is flourishing then the bacteria and mycorrhizal fungi can move nutrients and balance the soil for your plants without your help.
But what are the elements to creating a healthy soil ecosystem? To develop a healthy soil ecosystem for your plants the soil will need oxygen, water, a food source, minerals, and microbial life. Basically if you can maintain these 5 environmental conditions and then get out of the way, your soil life and therefore your plants will thrive.
Oxygen
The microbes in the soil need oxygen for their metabolic processes just like you and I. It is why when you turn the material in a compost pile you see it heat back up again. You added oxygen so the microbes can breathe again, and they get back to work breaking down the compost pile. The soil is no different. The microbes in your plant’s rhizosphere need oxygen to metabolize and transport minerals, and to break down dead organic matter in the soil. If your soil is too hard and compacted there won’t be much air, and therefore there won’t be much life. If it’s too wet and waterlogged it will go anaerobic and a whole different set of microbes will move in, and unless you are planting a rice paddy it isn’t going to work out well for you. As the microbes do their work they will give off carbon dioxide, and there needs to be space in the soil for it to escape.
Water
Every living thing needs water so this isn’t going to be much of a surprise. But we have water listed 2nd because the conditions that affect water levels in the soil are closely tied to the ones that affect airflow. Hard packed tight soil doesn’t breathe, and it also doesn’t absorb or hold water well. Have you ever spilled a drop of water on bone dry, hard packed, bare dirt and seen it just sit there in a bead without soaking in? The soil is too tight to absorb it. Water moves through the soil through capillary action. It is drawn through the in-between spaces between all the other materials in the soil. An example of capillary action is draping a towel on the edge of a bucket with the tip just sitting in the water. The water will slowly soak up the towel, against gravity, as it is drawn into the spaces between the fibers of the towel.
Imagine the water in your water table slowly being drawn up through capillary action in the soil to water your plants from below. But here is the kicker: it happens twice a day due to the same gravitational forces of the moon that cause the tide. As the moon passes it pulls the water levels up in the soil, and the water level recedes again as the “tide” goes out. As the water level moves up in the soil it pushes the air out, and all the carbon dioxide the microbes have exhaled along with it. As the water level recedes, fresh oxygen is drawn down into the soil to keep the microbes metabolizing. Water and oxygen are tied together because they are the lungs of the soil. Tight soil conditions that prevent breathing are “tuberculosis” for your soil system.
Food
“We need to understand that the microbes are foundational, and they need to be maintained 12 months of the year. There is not an off period where they can afford to not eat for 3 months.” – Dan Kittridge, “Principles of Biological Systems” 2 Day Seminar
The primary food source for the soil system is plant exudates during the warm growing season. The secondary source, especially in the north where we have cold winters, is organic matter covering the soil along with what is already built up in the soil. This is why it is important to maximize your growing season with multiple plantings. You might think extra plantings in a season would deplete the soil, but without plants in the ground feeding them exudates, the soil life will start depleting the organic matter in your soil as a backup food source. You want to keep living roots in the soil for as much of the growing season as possible. This is also one of the reasons I don’t really worry about weeds too much anymore. Weeds are just extra plants feeding and building my soil life. If I find Lambs Quarter I’ll pull it because it will get 6’ tall, but if I find Dandelions I’ll just treat them as a cut-and-come-again salad crop for my rabbits. The dandelions aren’t going to bother my snap peas one bit. My fall carrots this year are some of the best I’ve even grown in terms of consistent size, flavor, and pest resistance. Every square inch of both beds are overrun with a low growing wood sorrel and the carrots don’t mind at all.
In the cooler months, you will want to either plant a winter cover crop, or mulch heavily. The decaying mulch material will act as slow-feeding organic matter to keep the soil life healthy until warmer weather comes. For small scale and homesteading gardens there are a number of great options. Fall leaves can be collected at just about the right time to mulch all the beds and tuck them in for winter. Wood chips can be another great option, and they are even better if they have been sitting around for a year starting to break down. Grass clippings, hay, or straw can all be great options if you can verify they came from clean sources and did not have herbicides or pesticides applied to them. Mulching aisles between beds is also important because many of your plant roots will extend into the soil under these pathways so you want to feed those microbes as well. Besides being a food source, a heavy mulch layer also protects the soil year round. In the summer mulch greatly helps to retain water in the soil and minimize evaporation. I’ve gone 6 or more weeks at times without significant rainfall without needing to irrigate because of the mulch layer and high organic matter levels in the soil. Mulch also helps with water absorption by slowing rainwater and allowing it to soak in, instead of running off.
Minerals
Modern industrial agriculture is built around petrochemical derived fertilizers, herbicides, and pesticides. Most fertilizers used in farming (and also at your local garden center), are labelled with three letters with the major components of N, P, K (nitrogen, phosphorus, and potassium). Think of these as the macronutrients of the plant world, parallel to carbohydrates, proteins, and fats as the human macronutrients. They are important and needed by your plants in the largest quantities. However, if you are using farming practices that destroy the soil life and demineralize the soil over time, eventually all your plants are getting in sufficient quantities are the N, P, K in the fertilizer. It’s like a human, only eating fast food. Yes, you will get enough carbs, protein, and fats but you won’t be getting enough vitamins. Eventuall,y body systems will start to fail or downregulate leaving you open to diseases, and system failure. So we prop up our croplands with N, P, K fertilizers and then when the weak nutrient-deficient plants can’t defend themselves we spray pesticides and herbicides to “help.” Let’s face it, these plants are on life support. They aren’t healthy and they aren’t fit to eat. Diseases and insects that prey on plants are nature’s cleanup crew. The “pests” are there to remove the plants that aren’t fit for the environment so a different plant can take its place to correct the soil system. If the plants were healthy in the first place they never would have been a target.
A Side Note: The major shift to the agrochemical approach began after WW2 as the weapons suppliers of bombs and explosives needed a new market for their product. They used financial incentives to replace the heads of agricultural programs at many state universities and push the entire agricultural field towards their system and products to the detriment of our entire food supply. Remember the Oklahoma City bombing? It was a van full of fertilizer with an ignition system to turn it into a bomb. From bombs to fertilizer, and from fertilizer back to a bomb.
The basic minerals required for life must be present in the soil for the microbes to access or they will die. Deficiencies in the mineral content of the soil become the limiting factor for the soil life, and thereby the limiting factor for the health and productivity of your plants. As an example, the core of the molecule used by the azotobacter bacteria (the one that partners with legumes) to fix nitrogen in the soil is a molybdenum atom. If your soil is deficient in molybdenum the bacteria can’t make enough molecules to fix nitrogen for your plants. You will not see molybdenum on fertilizer bags, or most soil test reports. However if it isn’t there in small quantities your soil ecosystem will be broken. 1 pound per acre is enough to turn on the nitrogen fixing system in the soil life.
With an atmosphere made up of 78% nitrogen, why would we ever need to buy any for our plants? And yet the major component in most fertilizers is nitrogen. The trees in the forest don’t need anyone to add nitrogen, the grasses in the prairie don’t need added nitrogen, so why do your garden plants? You can listen to the agro-industrial complex and buy fertilizer to “fix” your soil, or you can ensure your soil has all the micronutrients that they need to flourish. I would argue that using fertilizers and pesticides to help your plants are like using band aids to stop arterial bleeding. The problem is in your soil system and the balance of minerals available to the microbes. Fix the balance, and the microbes will be able to make all the micronutrients available for your plants.
(To be continued in Part 3.)