So you would like to have a minerally balanced soil for optimum fertility? It will require an investment, but that investment will pay big dividends. Optimum mineral balance in the soil will result in:
- Increased nutrient density in the food and livestock forage you grow
- Natural disease and pest resistance
- Increased yield
- Improved soil tilth and friability
- Improved water retention and drainage
- Reduction in weed problems
- Reduction in fertilizer inputs
- Retention of Carbon and Nitrogen
- Ideal pH for your soil and climate
In the long run soil mineral balance will save you money by:
- Reducing the need for additional fertilizers
- Reducing water usage and providing protection in drought conditions
- Reducing pesticide and herbicide use
Additionally, you will be providing the highest quality, most nutritious produce, dairy, and meat possible for your family and customers.
The investment required to achieve such results consists of a soil test, a soil Rx based upon the results of that soil test, and the soil amendments needed. The quantity of minerals and amendments will depend on the condition of your soil, and how deficient the soil is in eleven primary and secondary mineral elements. For example, many soils in the United States are very Phosphorous deficient. Certified organic requires the use of amendments approved for organic use by the USDA National Organic Program.
Everything In Balance
The primary elements that are required in optimum levels are Sulfur, Phosphorus, Calcium, Magnesium, Potassium, Sodium, Boron, Iron, Manganese, Copper, and Zinc.
Justus Von Liebig, considered the founder of organic chemistry and regarded as one of the greatest chemistry scientists of all time, made major contributions to biological and agricultural chemistry. He popularized the “law of the minimum” which states the availability of the most abundant nutrient in the soil is only as good as the availability of the least abundant nutrient in the soil. To put it another way, a plant’s genetic potential is limited by the nutrient in shortest supply.
For example, too much Phosphorous restricts Zinc. Magnesium can stimulate the uptake of Phosphorus, while excess Potassium can inhibit uptake. If the Calcium level is too high in relation to Magnesium, the soil will be loose but will lose its texture and cohesiveness and water may drain through too easily and be lost. It will also be more prone to erosion from wind or water. If the Magnesium level is too high, the soil will be tight, preventing water and air from moving through easily. Too much Potassium restricts, or ties up, Boron and possibly blocks out the Manganese. High Copper shuts down Phosphorus, Zinc and Iron.
An optimum level of Sulfur is critical to the retention of Nitrogen and Carbon. Without adequate Sulfur, much of the ammonia Nitrogen generated by the breakdown of organic matter will be off-gassed into the atmosphere and be lost. Much of the Carbon will be lost as well as it is off-gassed as Carbon dioxide. (CO2). These are just a few examples of why ideal mineral quantities are so important. Rather like Goldilocks and the Three Bears, we want it just right.
Minerals and Human Health
If the minerals are not in our soils, they can’t be in our food. The secondary elements (secondary not in importance but in quantities required in relation to the primary elements) of Iron, Manganese, Copper, and Zinc play a vital role in health. Iron is essential for transporting Oxygen in the body and for the formation of red blood cells. It also supports the immune system and regulates growth. Manganese works in synergy with other minerals to promote immune system functioning. It is also necessary for reproduction, blood clotting, and for healthy skin, nails, and hair. Copper combines with certain proteins to produce enzymes that act as catalysts for skin pigmentation and the formation of collagen to maintain and repair connective tissues, including the heart and arteries. Zinc is the “reproduction and intelligence” mineral essential to neurotransmitter functioning and the maintenance of cognition. It is found in every tissue in the body and is essential for protein synthesis and cell division as well as being a powerful antioxidant. Zinc protects against neurodegeneration and the development of Alzheimer’s disease. Most agricultural soils in the United States are severely Zinc deficient.
One can see the necessity of these secondary minerals to human health. They must be in the soil in optimum quantities, and in balance, if they are to be in our food and in our bodies.
Insoluble But Available
Calcium, Magnesium, Potassium, Sodium, Iron, Manganese, Copper, and Zinc, are cations (KAT-eye-ons) and have a positive ionic charge. They are held on negatively charged exchange sites primarily in the clay portion of the soil, but also on the organic matter or humus portion of the soil, by an electrostatic bond (opposites attract). Sulfur, Phosphorous, and Boron are anions (AN-eye-ons) having a negative charge and are primarily complexed with humus (organic matter), which has both positive and negative charges. Boron and Sulfur (and even some Copper) can be subject to some leaching.
However, as organic matter increases, more Boron and Sulfur will tend to adsorb to the organic matter and thus remain in the soil and available to plant roots. Conversely, soluble synthetic fertilizers leach into ground water and run off into rivers, lakes, streams, and eventually into the ocean.
The exchange capacity of the soil is its ability to hold on to and release mineral nutrients. Put another way, it is the soil’s “gas tank.” A soil with a large gas tank will take you a long way. A soil with a small gas tank will need to be refilled more frequently. Both can be balanced for optimum fertility. The initial cost of bringing a soil into balance will depend on the size of its gas tank. The exchange capacity of a soil (the size of its gas tank) will determine the initial cost. A soil test will tell us the size of the gas tank. That is always where we begin.
Cost Range Per Each Soil Rx
The total cost of treating a garden, field, or pasture depends on how big the soil’s gas tank is, the total square footage or acreage, condition of the soil, what it is deficient in and the degree of deficiency, freight for bulk quantities, your geographic location, and prices for soil amendments from your local sources.
The cost of a soil test is $43. The cost for writing a soil Rx is $50. Custom amendment blending is $50. The cost of any additional consulting is $50 per hour. Soil amendments can range from $0.03 per square foot for farm acreages where bulk pricing is available to $0.35 per square foot for home and market gardens. Actual cost within this range is determined by the current condition of the soil’s fertility and the size of the field or garden being treated.
The cost of an ideal soil of optimum fertility does indeed require an investment. However, once the soil has been amended and brought into optimum balance, you will not have to amend in these quantities again. The soil will have everything needed for years to come. Yearly maintenance will involve the addition of Sulfur and Boron, two minerals that are readily taken up by plants and subject to some leaching.
By investing in “soil building” you will realize the most nutritious produce, forage, dairy, and meat possible. Your products will taste superior, be of superior quality, and therefore will command a premium price. Your family and your customers are worth it.
Next time, we’ll examine one of the gardens we’ve been working on over the course of two years, and share more details about investment and results.
In the first update on Mary’s garden, we reviewed a soil prescription and saw the broadcasting of the custom soil amendment blend in the fall of 2016. Mary is a veteran gardener from Minnesota and has been accustomed to good results. In the season prior to amending the soil in her new garden, she simply could not get anything to grow and was concerned that she had lost her touch. Of course, she had not. Her soil was quite deficient in eight of the eleven minerals necessary for plant growth, health, and reproduction.
Overall, Mary’s garden did much better than usual in 2017 with nice yields. Cucumbers, basil, beets, and potatoes did very well as did cabbage and broccoli. She also had a thriving patch of carrots.
However, after returning from a ten-day trip, fungus had infected the carrots and caterpillars had devoured the cabbage, cauliflower, kale, and broccoli. Peppers did moderately well, Cow Pea Coat and Jacket beans did very well while two other bean varieties succumbed to fungus. Mary had enough tomatoes to eat fresh but fungus prevented the canning she had planned for. Melons were mediocre.
There is no reason for alarm. These results, both good and bad, can happen in the first growing season after amending. They are also partly due to excessive rain just as Mary’s summer produce was ripening. The original mineral deficiencies and imbalances were quite substantial and correcting them resulted in some obvious improvement. However, this is a process that takes several growing seasons to see the full result of mineral balance.
The soil microbes have just begun their work in consuming and digesting insoluble minerals. The more they digest, the more they reproduce and die. This ongoing biological process of digesting, reproducing, and dying ensures that a steady supply of nutrients are returned to the soil in a form that is available to plant roots. With an abundant supply of minerals added to the soil for the microbes to feed on, biological activity increases and so does the availability of nutrient minerals.
As this process continues, so do improvements in plant quality, vigor, disease and pest resistance, yield, and nutritional value. Improvements will continue each growing season, as the minerals become increasingly plant available.
We will be taking a soil sample soon to see if we achieved ideal balance. Plants readily take up Sulfur and Boron, and Boron is also subject to some leaching. These two minerals will likely require a minor adjustment annually. Because Mary made the investment of bringing the soil into ideal balance, she will not need to add the other minerals in these quantities again.
Mary has done much more than balance the soil for optimum fertility and nutrient content of her food, she has done her part in reducing the amount of carbon dioxide released into the atmosphere. By providing optimum levels of Sulfur she has kept Carbon in the soil and out of the atmosphere. Without an adequate level of Sulfur, instead of Carbon being incorporated into the soil as stable humus, it will off-gas as Carbon dioxide. It’s the same with Nitrogen. As the organic matter applied to soil breaks down, it produces ammonia Nitrogen. Without the presence of adequate Sulfur, much of that Nitrogen created will be lost to the atmosphere as ammonia gas rather than utilized by crops. Keep in mind this is FREE Nitrogen from the atmosphere that we are losing! It is amino acid Nitrogen necessary for protein development, provided by Nitrogen fixation resulting from the microbial symbiosis that takes place around the roots.
We will continue to keep you updated on the progress by sharing the results of the soil test and the soil Rx showing any adjustments needed. Additionally, we will perform Brix tests on next year’s crops to monitor the increasing nutritional value of optimally amended soil.
When Nature speaks, we are wise to listen. Weeds have an indispensable purpose in our ecosystem. Nature uses them to tell us about the state of our soil fertility and the nutrients lacking, or overabundant in our soils. The weeds we are accustomed to despising can actually be our allies. In fact, weeds are not the problem. Rather, they are only a symptom of a larger problem.
Weeds have numerous purposes. They are nature’s way of covering bare soil to prevent erosion due to wind and water. They also exist to correct soil fertility deficiencies. For example, the common dandelion is an indication of a Calcium deficiency and Potassium excess in the soil. The dandelion has a very long taproot that can grow as deep as three feet into the soil, retrieving Calcium from below the root zone, and bringing it to the surface where it will be deposited as the plant decays. Canada Thistle tells us we may have a Calcium deficiency along with excess Phosphorous and Potassium. Many broadleaf weeds thrive in soil conditions where available Potassium exceeds available Phosphorous. (Ideally, we want Potassium to equal Phosphorous by weight.)
If you were to observe vacant land over time, you would see a “weed progression” indicating the nutrients lacking in the soil during a given period of time. Whatever nutrients are deficient, weeds needing to capture those nutrients will be dominant. Let’s say those nutrients are Calcium, Phosphorous, and Copper and you are having trouble with Jerusalem-oak and Oakleaf (Goosefoot). When enough Calcium, Phosphorous, and Copper have been brought to the surface and released, those weeds will be suppressed by others seeking nutrients deficient at THAT point in time, and on it goes.
If you were to have a soil sample analyzed it would most likely confirm the deficiencies of Calcium, Phosphorous, and Copper. Additionally, if you balanced the minerals in the soil and corrected the above deficiencies, the Jerusalem-oak and Oakleaf would not thrive. With soil nutrients in optimum balance, weeds will still exist but won’t be an onerous, insurmountable difficulty.
Weed seeds are tiny in most cases and don’t have the food store to sustain them during early growth like larger crop seeds do. Therefore, the weed seeds depend on soluble fertilizers for their early growth and will respond to those fertilizers by proliferating. Having optimum soil mineral balance will give crops what they require without the need to apply soluble salt fertilizers (NPK).
When addressing weeds in the garden or crop field it is best to do so before they go to seed. If you can, get them early when they are “in the white.” Whether you cultivate, cut, or mow them leave the residue on the soil surface. It will keep the ground covered and return nutrients to the soil as the weeds decompose.
Further problems may arise when adding a soil amendment without a soil test. In one instance, a farmer growing alfalfa added nearly 1000 lbs./acre of Potassium sulfate after having heard it would grow better alfalfa. Dandelions began to grow during the first year and after several years; the dandelions took over the alfalfa. Too much Potassium interfered with the uptake of Calcium in the root zone. The dandelions grew to reach deep into the soil to bring up available calcium. This illustrates why it is so important to get a soil test before adding anything to your soil. You must know where you are to determine where you need to go. It also demonstrates the effects of adding too much or too little of one mineral on other minerals.
We’ve just scratched the surface on the subject of weeds and what they can tell us. In addition to indicating soil mineral imbalances, an excess of weeds can help us improve our farming and gardening practices by encouraging the use of cover crops or fostering effective grazing practices. There are a number of excellent books on the subject of weeds. If you wish to investigate further, we highly recommend the following:
McCaman, Jay L. When Weeds Talk. 2nd ed. of Weeds and Why They Grow.
Retitled, When Weeds Talk. MO, 2013. Print.
Pfieffer, Ehrenfried E. Weeds & What They Tell Us. 3rd ed. Floris Books, 2012. Print.
Walters, Charles. Weeds, Control Without Poisons. 2nd ed. Acres USA, 1991/1999. Print.
According to the National Gardening Market Research Company, a widely recognized authority on the U.S. consumer lawn and garden market, “an estimated 90 million households participated in do-it-yourself lawn and gardening activities last year  – in and outdoors. That’s about 75-percent of all U.S. households. According to the survey, the most important market force was 18-34 year olds. Five million of the six million ‘new’ gardening households were Millennials.”1 How exciting is that!
We have talked to several clients over the years that were excited to get their children into vegetable gardening to teach them about the fun and function of growing their own food.
The report further states that Americans spent about $3.6 billion growing vegetables, fruit, berries and herbs.1 That’s quite an investment—but worth it if we consider the value of homegrown goodness for our consumption and overall health.
Planting day will be upon us before we know it. In our neck of the woods, this past winter season featured spring-like temperatures, prompting lots of garden plants to wake up a bit too early.
As spring begins, it’s a great time to get a soil test and evaluate the short-term and long-term needs of your soil. Whether you farm on a larger scale and prefer to use your own fertilizer dealer, or garden on a smaller scale and would like us to ship you a custom soil amendment blend, the first step is always a soil test. You must know where you are to get where you want to go. If you are having problems with weeds, low yields, poor quality, drainage issues, flowering, fruiting, seed development, or all of the above, we want to work with you to begin the process of maximizing the fertility, balance, and productivity of your soil.
Visit the Get Started page on this site and you’ll find a step by step guide to taking a soil sample and sending it to the lab. After completing all five steps, you’ll soon be on your way to producing greater yields of higher quality, more nutritious, crops and forages.
Feel free to email us from the Contact Us page and we will be happy to answer any questions you may have, and assist you in the process of improving the fertility and performance of your soil.
1 2016 National Gardening Survey, GardenResearch.com
The Mid-America Organic Association Conference and Expo was held here in Kansas City last week. Farmers, gardeners, agriculture experts, and consumers came from all over the mid-west to share their commitment to clean, healthy, chemical-free, naturally grown food crops. Manufacturers showcased many innovative and environmentally sound products and services. The exchange of information and ideas was incredibly inspiring and created an atmosphere that was nothing short of electric.
Each individual we spoke with had a passion for cooperating with Nature in the growing of our food and was firmly committed to healing and caring for the land. We met with speakers such as David Yarrow, sustainable farming researcher and advocate, and Joel Adams of Adams’ Osage Ridge Aronia Community Farm, who are both tireless in their endeavors to farm, research, educate, innovate, and bring together many schools of agricultural thought for the purpose of growing the highest quality food possible.
We were privileged to spend an hour with Jim Porterfield, a brilliant agricultural researcher who has been involved in cutting edge science and innovation in growing nutrient dense crops. We visited a number of vendor booths that featured products with an emphasis on trace minerals combined with humates and inoculants. We witnessed the “mineral message” gaining momentum among organic farmers and those who supply them with carbon building inputs.
We also met with farmers like Michelle from Illinois, mother and homeschooler of five, who was excited to learn about soil amendments and how they could help her transform an acre of clay-heavy soil into a minerally balanced, sustainable and diverse teaching garden for her children. And we met with Tasha from St. Louis, a community activist who is passionate about turning vacant urban lots with poor soil into community gardens. Frank LeBeau, Garden Educator with Heal the Planet Farm, stopped by to chat about the need for mineralizing the soil at their 350-acre organic permaculture farm located at the base of the Ozark Mountains in Southern Missouri, an area where traditional farm acreage suffers from depleted soil.
This diverse group of individuals and companies made it profoundly clear that healthy, nutrient-dense, sustainably grown, humanely raised food is imperative to the well being of our families and communities, our country and our planet. But paramount to all this, is the sobering truth that this can only be accomplished by us. Yes, US!
It will take consumers directing the resources of their pocket books toward the purchasing of this food. Our organic and biodynamic farmers stand enthusiastically ready to produce more and more for the growing demand. Existing organic markets will thrive and new ones will be established. Supermarkets will become dominated by ever-larger “organic departments,” until one day we are daily nourished by the quality of healthy food once enjoyed only by our ancestors.
These necessary changes in the way we produce our food cannot be left up to our government or multi-national agribusiness corporations. WE must direct their policies and actions. That which the consumer demands ultimately determines what is produced and how it is produced.
Mary had completed that all-important first step—taking a soil sample. The laboratory analysis had been received, the custom soil Rx had been written, and the soil amendment blend was created for her specific soil needs.
It was show time in the Wenger garden on December 4th as the soil amendment blend was broadcast over the loose soil and tilled in to the top six inches. That top six inches of soil, often referred to as the plow layer, is where most of the root growth and nutrient exchange takes place.
December 4th might seem to be a late date, but our mid-western weather was very mild this autumn, and Mary was pulling late season greens and potatoes from her garden well into November. The ground had not yet frozen, and she wanted to take advantage of winter snow and rain to help incorporate the new amendments.
Mary had actually delayed the operation by a day due to excessive wind, which can blow away many of the fines before they get worked into the soil. She watered the amendments in and covered the soil with a light layer of hay.
Bringing your soil into optimum balance does often require an investment. Mary utilized a wise option in soil balancing, which is to treat half of your garden, field, or pasture one year and the other half the next year. There are two main advantages to this. First, it spreads the cost over two years and second, it gives you an untreated (control) area that illustrates how much better the treated area produces in terms of quality, nutrient-density, and yield. Depending on the size of your project, you may decide to balance the soil incrementally over several growing seasons.
This time of year is a great time to peruse the seed catalogs that are coming out and laying some plans for the upcoming growing season. With that in mind, we discussed the benefits of keeping the soil covered at all times and how that sequesters carbon, reduces erosion, and provides free, amino acid Nitrogen for next growing season. Plans are being made for late winter/early spring cold hardy cover crops to be planted, providing that Nitrogen source as well as a “plant through mulch” after cutting down the cover crop before it goes to seed.
We will keep you updated with the progress of Mary’s garden. Till next time … #soilminerals #soilamendments #covercrops www.sustainablesoils.com
Last May, we had the pleasure of meeting a new customer, Mary Wenger, who along with her family raises her own produce on a 1,750 square ft. backyard garden.
We have often written about minerals and their importance to health, vigor, nutrient-density, and yield, and it was a pleasure to share this message with Mary in person.
With this in mind, we thought we would follow the progress of Mary’s garden to illustrate how mineral balance works, and what the results are. Beginning with an examination of the garden’s current quality and productivity, we will chart its progress and follow the improvements in crop nutrient-density and mineral content of plant sap through the use of a refractometer. We will also illustrate how a mineral balanced, biologically active soil greatly reduces and even eliminates weed, pest, and disease problems.
The first step, and it’s always the first step, is to get a standard soil test. You must know where you are to get where you want and need to go. As we move through the process of balancing Mary’s soil, we’ll post interviews with Mary and her family as we monitor the progress.
Let’s begin this journey by looking at the soil test results and the soil Rx showing what we need to bring this soil into optimum balance. Next time, we will examine in detail the soil amendments we use and what we accomplish with them. If you would like to see instructions on how to take a soil sample, and view more soil prescriptions, you can visit our website at: http://www.sustainablesoils.com/get-started/ and http://www.sustainablesoils.com/wp-content/uploads/2015/10/SampleSoilPrescriptions.pdf
Although the metal Manganese is gray in color in its pure form, the Incas called the reddish gemstone, rhodochrosite, Inca Rose, believing that this Manganese and carbonate-based substance was the blood of their former kings and queens turned to stone. Perhaps they had a clue as to how essential Manganese is to all living organisms.
Arden Anderson, doctor, farmer, and author of “Science in Agriculture,” long ago made the connection between nutrient-dense foods grown in mineral rich soils and the health benefits they offer us. He suggests Manganese provides the electrical charge that draws other elements into the seed. There is an atom of Manganese at the center of the germ of every seed and Manganese is necessary for reproduction through the formation of healthy seeds.
Manganese plays a very crucial role in plants and is necessary in nitrogen metabolism, photosynthesis, and the formation of other compounds required for plant metabolism. It also acts as an activator for more than 35 different enzymes. Manganese is a synergist with iron. They work together and need each other. An example of this interdependence is that high levels of available iron in the soil can limit the uptake of Manganese.
Manganese, proposed to be an element by Carl Wilhelm Scheele in 1774, was actually discovered by the Swedish chemist Johan Gottlieb Gahn when he heated the mineral pyrolusite (MnO2) in the presence of charcoal. Today, Manganese for agricultural use is obtained from pyrolusite by treating it with sulfuric acid (H2SO4) to form manganese sulfate (MnSO4), which is then electrolyzed.
Manganese is essential to all plants. However, certain crops have been found to be especially responsive to adequate levels of Manganese such as beets, cauliflower, citrus, lettuce, onions, potatoes, spinach, sweet corn, small grains, large-seeded legumes, alfalfa, sorghum, soybeans, cotton, and tobacco.
Manganese is not translocated in the plant so deficiency symptoms appear first on younger leaves. Interveinal chlorosis is the most common symptom and in severe cases, a series of brownish-black specks appear in the affected areas with eventual premature leaf drop. Delayed maturity is another deficiency symptom in some species. Manganese deficiency is prevalent in calcareous soils, high pH soils, and soils with excessive levels of organic matter. Excessive levels of Calcium and Magnesium can also interfere with Manganese uptake.
Manganese toxicity can become a problem in soils deficient in Copper and Zinc. The late John Mark Purdey, an organic farmer and brilliant researcher, found that bovine spongiform encephalopathy (BSE) or mad cow disease and chronic wasting disease, are directly correlated with soils very low in Copper and Zinc in combination with high levels of Manganese. In this worldwide study, he discovered that BSE and CWD may not be the result of viral infections but the result of a mineral imbalance.
Both animals and humans require Manganese. In humans, Manganese activates the enzymes necessary for the body to use biotin, thiamine (B1), vitamin C, and choline. It’s also needed for healthy nerves, immune system function, blood sugar regulation, formation of mother’s milk, and the growth of healthy bones. Deficiency may lead to trembling hands, seizures, and lack of coordination. Manganese is a co-factor for an enzyme called manganese superoxide dismutase (MnSOD), an antioxidant associated with protection against free radical damage. Conditions marked by increased free radical damage to cells and tissue have been linked to diets low in manganese. In animal nutrition, an excess of manganese increases the need for iron, and a manganese deficiency results in leg deformities in calves, eggs not formed correctly, degeneration of testicles, offspring born dead, and delayed heat periods. An excess of calcium and phosphorus may lead to a manganese deficiency.
It is quite clear that animals and human beings need adequate levels of Manganese. For this to occur, it must be in the soil in adequate levels and in optimum balance with Sulfur, Phosphorus, Calcium, Magnesium, Potassium, Sodium, Boron, Iron, copper, and Zinc. For all of this to work and result in maximum animal and human nutrition, trace elements such as Chromium, Cobalt, Iodine, molybdenum, Selenium, Tin, Vanadium, Nickel, and Fluorine must also be present in tiny amounts. Deficiencies in these trace minerals can also be problematic but that’s a different story for another time.
Astera, Michael. With Agricola. The Ideal Soil 2014: A Handbook for the New Agriculture v2.0. Michael Astera, 2014. Print.
Walters, Charles, and C. J. Fenzau. Eco-Farm. Acres USA, 1996. Print.
Andersen, Arden. Science in Agriculture. Acres USA, 2000. Print.
DVM. Skow, Dan, and Charles Walters. Mainline Farming for Century 21. Acres USA, 1995. Print.
Fallon, Sally, with Mary Enig. Nourishing Traditions. New Trends, 2001. Print.
Phosphorus was the 13th element to be discovered, and the first that was not known since ancient times. For this reason, and also due to its use in explosives, poisons and nerve agents, it is sometimes referred to as “the Devil’s element.”1, 2 German alchemist Hennig Brand is credited for discovering this element in 1669 when he distilled approximately 5,500 liters of human urine to produce 120 grams of a glowing substance which he ultimately named Phosphorus, from the Greek word for “light-bearing.”
For over a century, Phosphorus has had multiple functions in soil chemistry. Today we know that optimum levels of Phosphorus enhance early root formation and growth, flowering and seeding, uniform crop maturity, and stalk and stem strength. It is important for photosynthesis and respiration. Respiration is the process by which plants convert photosynthates such as sugars, back into energy for growth and other metabolic processes.
Soil Phosphorus is immobile for the most part and the level of soluble Phosphorus immediately available to plants is rather small. In order for plants to satisfy their need for Phosphorus, their root systems must explore large areas of soil. Mycorrhizal fungi greatly assist plant root systems in this exploration by forming a symbiotic relationship with them. The thread-like hyphae of the fungus connect with plant root hairs and extend great distances into the soil, taking up nutrients and transporting them back to the plants. This results in increased Phosphorus uptake. In exchange, the mycorrhizal fungi receive sugars and other compounds from the roots.
The uptake of Phosphorus can be limited by soil compaction, pH, and moisture. Even in high Phosphorus soils, anything that inhibits aggressive root growth, such as compacted soil, will have an adverse effect on Phosphorus uptake. With a pH greater than 7.0, Phosphorus can be fixed in less available forms by excess Calcium. With a pH of less than 6.0, Phosphorus can be fixed in less soluble forms by excess soluble Aluminum. Phosphorus availability is at its highest at pH 6.4 to 6.8. Optimum levels of Phosphorus will result in higher Phosphorus uptake at all moisture levels. However, moisture stress results in lower Phosphorus availability. Moisture levels exceeding soil capacity exclude the oxygen required for Phosphorus uptake.
Phosphorus is a highly reactive element and does not exist in elemental form in soil. Plant roots take up nearly all Phosphorus as phosphate. (P2O5) Orthophosphate is the simplest phosphate with the chemical formula PO4-3. Primary orthophosphate has a chemical formula of HP204–, is dominant in acidic soils, and is taken up much more readily than the secondary form, HPO42- that is the dominant available form of Phosphorus in alkaline soil conditions. All Phosphorus sources added to soil must be converted to the orthophosphate forms before plants can utilize them.
Organic, biodynamic, and biological farming/gardening practices utilize a direct application of rock phosphate as the source of Phosphorus. Colloidal soft phosphate rock and Tennessee Brown Phosphate rock are inexpensive, commonly available Phosphorus sources, both of which are approved for organic use by the USDA National Organic Program. Phosphate rock is a largely insoluble, slow release Phosphorus source. Only about 3% orthophosphate is soluble and readily available to plants. The rest remains “locked up” or chemically bonded to Calcium and is gradually released for plant use by the action of soil microbes. So the Phosphorus is long lasting, remains insoluble and in reserve, and is not subject to leaching. Optimum levels of phosphate rock in the soil contain enough “reserves” to provide the release of available Phosphorus in more than adequate quantities for early season requirements, as well as a continuous supply throughout the growing season.
Phosphate rock is also the raw material used to make highly mobile, water soluble Phosphorus fertilizers (WSP fertilizers) used by large scale farming operations. The global fertilizer industry consumes nearly 90% of the world’s phosphate rock production in the manufacture of WSP fertilizers. The remainder is used to make elemental phosphorus and animal feed supplements, or is applied directly to soils. Phosphate rock and sulfuric acid are the raw materials used in the manufacture of single superphosphate (SSP) and phosphoric acid. Phosphoric acid is an intermediate by-product used to make triple superphosphate (TSP) and ammonium phosphate. Highly concentrated, compound NPK formulations now form the mainstay of the global fertilizer industry (Engelstad and Hellums, 1993; UNIDO and IFDC, 1998).
Unfortunately, the high solubility of these concentrated NPK fertilizers, and their overuse in efforts to achieve huge yields of big, tall, expanded but nutrient deficient crops, is very detrimental to our environment. Unlike phosphate rock, which stays in the soil and releases its “reserves” of Phosphorus over time, superphosphate fertilizer is subject to leaching and runoff. Extensive use of concentrated NPK fertilizers destroys microbes, earthworms, and other beneficial soil organisms. The soil loses its beneficial texture and becomes less capable of absorbing water. Topsoil erosion becomes problematic and the runoff of rain carries soil particles, and the Phosphorus attached to them, into streams, rivers, and lakes.
Unnaturally high Phosphorus levels in these bodies of water fuel excessive growth of algae. In a process called “eutrophication,” these algae die, and are decomposed by bacteria that use dissolved oxygen. This creates “dead zones” resulting in fish kills, surface water scum, decreased recreational use, and foul odors.
Most phosphate rock is mined using large-scale surface methods. Michael Astera of Agricola has written one of the most insightful concepts regarding the mining of all minerals used in agriculture. It appears as follows:
“Mining of the needed minerals need not entail long-term environmental damage
either. Mines and quarries can be carefully worked by those who care about their
home planet, and when the mines are depleted they can be landscaped and
planted to be as or more beautiful than before mining. It’s also worth noting that
many of the economically viable sources for agricultural minerals contain such
high concentrations of these minerals that they are toxic to soil life and little or
nothing grows there. Removing these toxic concentrations and using them to
make other parts of the planet healthier and more productive can, at the same
time, open up these formerly toxic soils to the growth of forest or grasslands.
None of this should be done on the basis of greed or short-term gain, but rather
wisely, intelligently, and in harmony with Nature.”
Phosphorous, when present along with 10 other important minerals, all in ideal ratios to each other, results in a fertile soil capable of producing vigorous, nutrient-dense crops of superior quality. Such a mineral balance also works to sequester carbon, improve soil texture and drainage, provide adequate water retention, prevent erosion by water or wind, promote biological activity, and reduce costly annual inputs. Balancing the minerals in the soil is the first step toward sustainability because if the minerals are not in the soil, they can’t be in the food or recycled on the farm or in the garden.
Organic, biological, and biodynamic farming and gardening systems strive to reduce “outside inputs.” Once the minerals in the soil are balanced, you won’t have to add them in those quantities again. A soil test in the spring and fall will indicate any minor adjustments needed. Sulfur and Boron will be the minerals most likely needing attention as plants readily take them up. The superior health of a minerally balanced soil greatly reduces the need for inputs other than these minor adjustments. Since the minerals are in the soil, they will be in the crop residues, cover crops, and livestock manure and will be recycled through these sustainable systems.
Justus von Liebig, considered to be the founder of organic chemistry, popularized The Law of the Minimum. “The availability of the most abundant nutrient in the soil is only as good as the availability of the least abundant nutrient in the soil.” Whichever nutrient is in the shortest supply will limit the performance of the crop. This illustrates why balance, and optimum quantities of mineral nutrients, is so vital.
The Farming Systems Trial (FST) at Rodale Institute, is America’s longest running side-by-side comparison of organic and conventional agriculture. Over thirty five years of scientific data from the FST have proven that organic systems produce yields equal to conventional, outperform conventional yields in years of drought, build rather than deplete soil, and are actually more profitable than conventional farming.
We have focused on Phosphorus and its importance to sustainability. We have discovered that it takes a synergy of Phosphorus and ten other mineral nutrients to maximize soil fertility, and we have looked at just a few of Rodale Institute’s FST empirical, scientific findings. Moving forward in sustainability calls for the coming together of many ideas, scientific facts, and schools of thought.
1 Emsley, John (7 January 2002). The 13th Element: The Sordid Tale of Murder, Fire, and Phosphorus. John Wiley & Sons. ISBN 978-0-471-44149-6. Retrieved 2016-08-26.
2 Weeks, Mary Elvira (1932). “The discovery of the elements. II. Elements known to the alchemists”. Journal of Chemical Education. 9: 11. Bibcode:1932JChEd…9…11W. doi:10.1021/ed009p11.
“We know more about the movement of celestial bodies than about the soil underfoot.”
– Leonardo DaVinci
Biological activity in the soil is imperative to the development of vigorous, disease- and pest-resistant crops in the garden or field. Fungi, and bacteria are beneficial soil organisms that have a symbiotic relationship with the plant through its root system. They also play a major part in the breakdown of organic matter and the freeing of nutrients that may be in the soil, yet unavailable to plant roots. Some fungi even produce antibiotics that protect the plant from disease.
95% of plant species have a relationship with fungi. Mycorrhizal (my-ko-rize’-ul) fungi have an elaborate root system of fungal filaments that grow yards, both deep into the soil and in the root zone. Several miles of these filaments can be found in a few grams of soil. Mycorrhizal fungi seek out moisture and nutrients and bring them back to the plant roots. Therefore, the surface absorbing area of plant roots can be increased hundreds of times.
Myco means fungus. Rhizae comes from rhizome, meaning roots. This translates into fungus root. There are two types of mycorrhizae, (my-ko-rize’-ee) Endo-mycorrhizae, and ecto-mycorrhizae. Endo-mycorrhizae (meaning inside) actually penetrate the tiny root hairs of plants without changing the root’s cell structure, effectively extending the plants root system. The fungi bring moisture and nutrients back to the roots and in turn, the roots share sugars and other carbohydrates with the fungi. The fungi also release powerful enzymes that dissolve, and make available, nutrients that are tightly bound and difficult to access. Phosphorous, for example, a very active mineral with a strong negative charge can bond with Calcium, which has a double positive charge. The result is Calcium phosphate, a very stable compound. The enzymes break the Calcium/Phosphorous bond making the Phosphorous available for uptake by the plant roots. 90% of cultivated plants have a symbiotic relationship with endo-mycorrhizae.
Ecto-mycorrhizae fungi (meaning outside) grow next to plant roots but live completely outside of the roots. They share nutrients with the plant roots through the soil water/nutrient solution.
Certain types of bacteria, called rhizobia, live in symbiosis with legumes such as red clover, cowpeas, and alfalfa. These bacteria form and inhabit nodules on the roots of legumes and are able to take Nitrogen from air in the soil and create ammonia, which the plant uses to create amino acids and other compounds. The rhizobia in turn receive carbohydrates from the plant. These Nitrogen-gathering or Nitrogen-fixing bacteria are not found on common crop plants except legumes. Green manure is a rich source of Nitrogen for the soil and comes from turning these legumes under in your garden or field.
Some soil inoculant products contain numerous species of endo-mycorrhizae, ecto-mycorrhizae, and beneficial bacteria. When used, the species that are right for a given soil and climate will adapt and thrive. Soil inoculants increase the capacity of roots to absorb water and nutrients resulting in improved plant vigor, health, quality, and yield.
Whatever crop you are growing, enhancing biological activity in the soil vastly improves the crops capacity to reach its full genetic potential. Soils that are out of balance and lacking in needed minerals will most likely have a limited amount of biological activity. But when mineral nutrients are balanced and brought up to optimum levels, the fungi and bacteria will have something to work on and the soil will come alive. Using biological activators, or soil inoculants, will enhance and expand that activity by ensuring the bacteria and fungi that will best adapt to the soil and climate are present.
Bring your soil into balance with a custom soil prescription and amendment blend. Check out Step One to get started.