Soil Minerals and Soil Testing for Organic Gardeners


The excerpts below are from the Chapter 1 of
The Ideal Soil

The Ideal Soil: A Handbook for the New Agriculture

Chapter 1

The New Agriculture: What It Is, and What It Is Not

How did we end up where we are with our food supply today? Most would admit it looks pretty grim. Setting aside looming food shortages and price inflation worldwide, how did we end up with such abysmal nutritional quality coupled with high levels of noxious chemicals and compounded by deteriorating agricultural soils around the world?

Unsurprisingly, it has the same roots as our present abysmal economic prospects, being rooted in short-sighted greed coupled with ignorance and manipulated for the benefit of a few at the expense of the rest. Unlike economics, however, who stands to gain when the whole of humanity is ill and malnourished? Not humanity, that's for sure.

The wealthy may have more money and more security, but their food is no better than that of the average peasant and often worse. The falling tide of nutritional quality in food has left everyone's boat high and dry. Surely the wealthy aren't starving for bulk of food, but they suffer from the same diseases of malnutrition and toxicity as the rest of us do, namely cancer, diabetes, heart disease, and the various auto-immune diseases ranging from MS to AIDS. Whether dining in the fanciest restaurant or the poorest hut, nutrient deficiency and toxic overload are on everyone's plate.

This is the situation bequeathed to us by a century and a half of the increasing dominance of agriculture by a corporate industrial model focused solely on yield and profit. The truth of these observations is undeniable to anyone who looks objectively at world agriculture today. There are other schools of agriculture that have rejected the chemical industrial model and deserve great credit for their struggle to grow clean food and create a healthy environment in harmony with Nature.

On the following pages we will take a look at where, in our opinion, the alternatives too fall short of the goal of being truly sustainable or providing the best possible food. We will also learn a little of the history of mineral balanced agriculture and it's present role in world food production. None of the following is meant to offend, but it is not sugar coated.

What The New Agriculture Is Not

All of today's agriculture movements clamor that they have the answers, but do they? This writer thinks not.

The "better living through chemistry" factions are still flogging their tired horse. Having stripped the soil of its richness, burned out the humus and killed off the soil life, and having turned much of their not-so-little corner of Nature into a nutrient depleted toxic wasteland, they are now developing Frankenstein's monster crops, genetically modified organisms or GMOs, bred to live in these conditions. We can count on this turning out as well as their previous bright ideas.

This book is all about science and chemistry, but science and chemistry in the service of humanity and in harmony with Nature, not science and chemistry misused in a vain attempt to exploit and beat Nature into submission.

Humans are a self-aware and intelligent land animal. We have eyes and ears and brains; legs and arms and hands with opposable thumbs. We have the ability to understand the present and envision the future. Our role should be that of caretakers of our home, as we are the only ones who can do that. An intelligent person does not cut down the tree that shades their house from the hot afternoon sun or pour sewage in their family's drinking water, Attempting to exploit our only home for short term gain makes no logical sense; obviously it hasn't worked, isn't working, and won't work in the future.

The worldwide Organic agriculture movement and its various offshoots have so far only offered simplistic solutions, mostly one simplistic solution: add more organic matter to the soil. This is the school from which this book's authors come, and most growers with whom we work are organic growers. “More organic matter” is a step in the right direction if the soil is low in humus, but does little to address nutritional deficiencies, especially mineral deficiencies. Yet it is fiercely defended and proclaimed to be “the answer” for everyone everywhere. Is it? No. While essential, soil biology and organic matter are only a part of what makes a healthy soil and nutrient dense crops. Nature is not simple, and simplistic one-size-fits-all answers are not going to solve the nutritional and environmental crises we face.

Those who follow the Biodynamic school are to be commended for their deep appreciation of Nature and for having preserved much traditional knowledge and brought it into the present. They have an understanding of energy that goes far beyond simple electrical current flow, but by not fully understanding the minerals in their soil, they limit their potential.

Permaculture works fine in many instances, but is mostly an approach to stabilizing the existing soil, preventing erosion. Under a permaculture system the nutrients that are in the soil are largely retained; what is taken away is supposedly replaced with a fresh layer of organic matter. If every bit of the crop that was taken away was somehow brought back and replaced, the soil nutrient content would still only be what it was to start with, which in the case of most agricultural soils is far from ideal.

The various fans and promoters of soil biology, from earthworms to fungus, tell us that a bio-active soil will break down toxic residues, increase humus, and the beneficial soil organisms will make minerals and nutrients available to the plant. The question that is not asked is “what if the needed minerals are not to be found in the soil?”

The newer high-tech solutions, such as hydroponics, or even newer, aeroponics, rate a careful examination. Can we count on them to rescue agriculture? Not if the goal is to feed the world's people and animals. They are fine for growing some pretty tomatoes to sell at the supermarket, or some nice lettuce in the basement, but these "new and modern" systems have a number of basic problems, some of them insurmountable if the goals are sustainability and nutrient-dense food. The most obvious failing is that they are energy-hungry. They use pumps and fans and often lights. In the interests of self-sufficiency, where is that energy to come from? If the power goes out is one going to pedal a bicycle generator to keep the pumps and fans going? In addition to being energy-hungry, both hydroponics and aeroponics require special containers, growing solutions, training and handling. They are not automatic.

There are other not so obvious problems with hydroponics. Any time one has a liquid-based growing solution they need water-soluble fertilizers, and these must be pure. One does not put compost in the hydroponic trays. This makes all natural organic hydroponics pretty difficult. Another drawback is that only certain crops are suitable, mostly the ones you have seen in the stores so far: lettuce, tomatoes, peppers, and some herbs. One will not raise a field of potatoes, cassava, or turnips hydroponically, nor thousands of acres of grains and legumes. One will not grow hay to feed animals hydroponically or aeroponically.

The most serious downside to these systems, though, is the lack of nutritional completeness in the produce. Designer vegetables grown in nutrient solutions are grown for looks, not nutrition. No one has yet shown that a nutritionally complete diet can be grown in this artificial manner.

Mention should be made of the ultimate closed-environment theory of the day (or decade), the all-in-one fish pond and hydroponic garden. As you may know, the idea is that one raises fish in a pond, then uses the fish water to irrigate the hydroponic troughs. The nutrients from the fish water are used as fertilizer for the plants. The water comes out "clean" at the other end and is recycled back to the fish pond. Various theories suggest what the fish eat, but the grower gets to eat the fish and the vegetables. The theory sounds good, but all the designs seem to require glass or plastic domes. We will not feed ourselves and heal our polluted environment by creating isolated bubbles in the landscape.

The high-tech systems above are things to learn from and we will and have gained knowledge from them. One valuable contribution is that we know more about what mineral nutrients are absolutely essential for plant growth. These systems, however, are not suitable for feeding your family and community, and they will not form the basis of the New Agriculture.

The place to grow a crop is in the earth, in nutrient rich, biologically active soil, not in metered nutrient solutions; under natural sunlight, not electric lights. Sunlight is very energy-dense and plants are good at using it. Sunlight is also free. Within the limits of one's climate, one can create micro-environments that maximize solar gain, and one can choose crops that do well under one's local conditions. In Alaska and Finland, one might choose to grow cabbages, not melons.

The New Agriculture will not come about through dogmatic insistence on simplistic solutions such as adding organic matter to the soil, nor through force-feeding of synthetic fertilizers and applying toxic rescue chemicals to address the inevitable problems. The answers will not be found in energy intensive technology or artificial micro-environments. The solutions certainly won't be found by refusing to look outside whatever ideological box one has adopted or been convinced to adopt.

The New Agriculture

What we have today is a fragmented agriculture, yet we needn't be suffering this collective delusion and separation; it serves no useful purpose for mankind or Nature but only divides us. So here's a proposal: What if we were to take agriculture to another level, a higher level, by pulling together the best from all of modern knowledge, and combining it with the traditional wisdom accumulated over the span of human history? If we were to include the sciences of soil chemistry and nutrition (new tools in the 10,000 year history of agriculture), with a modern understanding of soil and plant biology (also new tools), and our modern knowledge of energy, both electromagnetic and subtle? The only questions we need ask are: What works and will continue to work, and what hasn't worked in the past or doesn't work now? No special emphasis would be laid on any one dogma or school of agriculture; the focus would be on soil health, nutrition, sustainability, and efficiency. The emphasis would be on constant improvement in health: of the land, the plants, the animals, and the people.

We would be looking for a system that works well with any crop in any climate, producing high yield, high quality, and high nutritional values while sharply reducing insect and disease problems. The plants would thrive and be superbly healthy because they would have all of the nutrients they desire available free-choice. The immune systems of the plants and soil would be strong and healthy; insects and disease are not attracted to strong, healthy plants. The animals and people consuming the plants would get the most highly nutritious food it was possible to grow. People wouldn't overeat because their body wouldn't be craving an essential mineral, carbohydrate, amino acid, or lipid. Diseases such as diabetes, cancer, heart disease, and the auto-immune diseases would become things of the past. Children would grow up able to develop to their full genetic potential; their intelligence and strength would no longer be limited by malnutrition or toxic chemicals. Fewer acres of cropland could feed more people and animals, sustainably, as the emphasis shifted from quantity to quality.

Unbeknownst to most, the basis of this new agriculture already exists and has for some time. The knowledge of how to accomplish the goals mentioned above has largely been known for over sixty years. The basic science of soil mineral balance and its relation to health and nutrition was discovered long ago, but has been buried and ignored. It has been hidden from the schools and practitioners of agriculture, both so-called "conventional" and the various alternative schools. It is not mentioned, or mentioned disparagingly in university ag colleges. Many "alternative" growers have never heard of it. Those who have heard of it but don't understand it and have never tried or experienced it nevertheless have opinions on why it couldn't work. We are in the situation of having the answers readily available but blindly refusing to see them.

Much of the work this mineral balanced agriculture relies on was done in the 1920s, '30s. and '40's. During the depression era of the 1930s there was a strong emphasis on finding out what went wrong in agriculture that led to the dust bowl years and a general decline in the health of American soils and people. Scientific nutrition was a new field and many exciting breakthroughs were made. By the late 1930s and early 1940s great strides were being made in both soil and animal health.

Along came WWII, and the food producers (farmers) were urgently needed; they were recruited by the government and made part of the war machine, subsidized by guaranteed crop prices, and were encouraged to innovate. The end of WWII saw most of the economies of the industrialized world dominated by the factory production model, much of it war-related. After WWII this industrial model was re-directed into the production of goods, machinery and chemicals for peacetime.

By 1950 it appeared to be a brave new modern world, one where all problems could be solved by dominating Nature, rather than learning from and cooperating with her. Big chemical companies took over the land grant universities and started really pushing their chemical-based agriculture. Most of the farmers eagerly adopted the new model; no longer were they just farmers, they were modernized commodity factories on the cutting edge of science. Or so they thought. While the yield went up, the nutritive value fell, and the plants force-grown on soon-depleted soil were insect and disease magnets, calling for more chemicals every year. The harsh concentrated fertilizers burned up the humus in the soil and killed off soil life. The soils were robbed of their mineral stores, as the only nutrients applied were those necessary to achieve high yield. The animals (and people) raised on these force-fed foods became malnourished and disease-prone. The law of diminishing returns was showing up with a vengeance, but the "scientific" solution to the problem was always another and more powerful chemical and a plant bred to tolerate it.

Meanwhile, still shortly after WWII, J.I. Rodale started the organic gardening movement in the USA, inspired by the work of Sir Albert Howard and Lady Eve Balfour in the UK, while William Albrecht was proving the validity and value of mineral balanced agriculture. William who?

The late William A. Albrecht, PhD, and his crew of researchers at the University of Missouri agricultural station were responsible for developing the mineral basis of the New Agriculture: the concept of balancing the alkaline nutrients in the soil based on the soil's capacity to hold them. In the 1920s they decided to take a close look at the various mineral fractions of soil: the clay, silt, and sand fractions. They took some of the local soil, removed the organic matter, and spun it in a centrifuge to separate it by size and weight. This yielded an almost clear, jelly-like layer on top that turned out to be made up of incredibly tiny clay particles, particles too small to be viewed by most microscopes. They were so tiny that they stayed suspended in water and wouldn't even centrifuge out, though they didn't dissolve. Colloids are what this type of particle is called; this was colloidal clay. What did these tiny bits do in the soil? It turned out they did a lot. Those colloidal clay particles were the basis of the soil's cation exchange capacity. They stored the alkaline nutrients in the soil, held by a simple static electrical charge, safe from being washed away, yet readily available to soil life. The plants and soil life traded +charged Hydrogen ions for these + charged nutrients. Albrecht and crew spent the next three decades experimenting with various combinations of mineral nutrients, growing the crops and feeding them to animals, measuring the nutritional value of the crop and the health of the animals.

However, by the late 1950s and early '60s the big chemical companies had managed to take over most of the USA's agricultural schools. They offered to fund new buildings and research projects, and pay for new professorial chairs, but Professor Albrecht and the other holistic researchers from the 1920s, '30s, and '40s had to go. Albrecht had demonstrated that the chemical companies' approach was an unnecessary path to bankruptcy and destruction and he wasn't about to teach their party line, especially as he had developed and spent years proving a better system that was sustainable and healthy. Albrecht was forced into retirement in the 1960s; his work was buried and would have been lost if not for the efforts of economist and editor Charles Walters, who started the magazine AcresUSA in 1970 to promote Albrecht's ideas. Charles Walters called this new science of balancing the cation minerals in the soil Eco-agriculture. It has been implemented on hundreds of thousands of acres of commercial farms in the US and Australia with great success, but the mineral balancing message hasn't yet gotten to the home gardener or small producer, nor has it gotten to the various branches of alternative agriculture. The corporate-dominated State Agriculture Colleges pretend it doesn't exist.

J.I. Rodale worked with Wm Albrecht and Louis Bromfield at Bromfield's Malabar Farm in Ohio during the late 1940s. Bromfield was working to restore worn-out farmland by applying Albrecht's mineral balancing principals as well as the organic ideas of the English agriculturist Sir Albert Howard. The story is that Rodale had a falling out with the Malabar farm group over the use of some man-made fertilizers that the others considered not to be harmful, probably ammonium sulfate. Rodale was a purist and his version of organic had no room for input that wasn't 100% natural. Sir Albert Howard taught that trees and other deep-rooted plants would bring up any minerals needed, and didn't give it a lot of thought beyond that. Rodale was convinced that leaves from deep-rooted trees, and rotting vegetable matter in general, could supply all of the nutrients plants needed to thrive, even in poor or worn out soil.

Rodale went on to found Organic Farming and Gardening magazine, today's Organic Gardening magazine, and for the first ten years almost all he wrote about was organic matter; mulch and compost were all anyone needed, he seemed to think. Only later, starting in the 1960s, did he begin to acknowledge the role of minerals and recommend them, particularly rock phosphate, greensand, and dolomite lime; but ordinary garden lime, Calcium, was seen merely as a pH adjuster, instead of being recognized as the single nutrient needed in most quantity in the soil that it actually is. J.I. Rodale was a man with a mission, and all of us who learned from him owe him great honor. He was almost single-handedly responsible for inspiring the strong and vibrant organic agriculture movement in the USA and around the world today. Anyone whose education in gardening was in the Rodale school, however, is going to know that minerals are needed, but is unlikely to know why or how much or where they come from.

Meanwhile, Albrecht's mineral balanced agriculture, as promoted by Walters in the AcresUSA newspaper and a number of books, moved forward through the 1980s and '90s, but only on good-sized farms, and few enough of them. Very few of the farmers using the mineral approach knew much if anything about the organic crowd. Balancing soil nutrients based on the soil's exchange capacity worked and worked well, and when a farmer had had enough of chemicals and poisons, or saw his neighbor growing better crops than he while working less and spending less, many did apply Professor Albrecht's principles and they continue to do so today. I have heard of no one switching back to their earlier style of farming, gardening, or ranching once they have experienced the results of a mineralized, balanced soil.

Another important person in bringing the knowledge of mineral nutrition to agriculture was the late Carey Reams, PhD, who did most of his life's work in Florida, USA. The Albrecht and Reams schools have slightly different but easily reconciled philosophies; they agree on the mineral balance, but often use different explanations and terms. Students of Carey Reams and Wm. A. Albrecht, and the students of their students, make up most of the mineral-aware agricultural consultants around today, worldwide, including this author.

Organic gardening, unfortunately, was stuck back in the 1950s, and it has largely remained there since: Compost, manure, mulch, and that's about it. The other schools of alternative agriculture - Steiner's Biodynamics, Permaculture, Elaine Ingham's Soil Food Web concept, the various miracle microbe schools etc.- all emphasize the biological and compost-based approach almost exclusively. The occasional mention is made of rock dust, phosphate rock, or dolomite lime, but seldom with any understanding of the soil chemistry involved.

The one truly mineral-oriented school of "mainstream" alternative agriculture is what I call the Glacial Rock Dust school, based on the famous 1982 book The Survival of Civilization , whose authors argued that the retreat of the glaciers at the end of the last ice age was the last time our soils had a fresh dose of minerals. Their solution was to add freshly ground rock powder to the soil as the source of those missing minerals, but there is little understanding of the actual role of minerals, and no conception of the amounts or balance of minerals needed. A average everyday soil with a cation exchange capacity of 10 requires around 3,000 lbs of Calcium in exchangeable form per acre, and 50 or so pounds of Zinc. Is that in the rock dust or not? Does the soil need the minerals in that particular rock dust at all? Freshly ground rock dust is a great soil amendment, but it can't be counted on to correct a mineral imbalance or deficiency.

What the USA ended up with by the 1970s was a great division between those practicing organic agriculture and those farming with strong, concentrated chemical fertilizers, pesticides and herbicides. Neither side talked to the other, the organic group taking the moral high ground against poisoning the land and the chemical farmers deriding the organic followers as backwards Luddites. Neither side knew about the successes of those using the methods of Albrecht or Reams. How could they? Organic Gardening was heavily invested in the idea that organic matter and soil biology alone were the answers, while the chemical farmers were convinced that the next hybrid crop and the newest pesticide were going to solve their growing problems. Neither one was interested in learning that they were both wrong, that there was a system already up and running that didn't require scores of tons of compost and manure per acre and didn't need toxic rescue chemistry either.

Our Story Continues Today

Back at the corporate laboratories and bought-off State agriculture colleges, the dyed-in-the-wool chemical farming fans are still trying to prove that the growing of food can be forced into an industrial production model. Their version of "working with biology" up until the 1990s was hybrid crops, and has now morphed into GMOs, genetically modified organisms. Both the hybrids and the GMOs are usually plants that have been bred to live on a starvation diet of NPK fertilizer while being regularly doused with herbicides, fungicides, and insecticides. Yield, disease resistance, the ability to survive repeated dosing with noxious poisons---these are the goals of the mad scientists leading corporate chemical agriculture. The health of the soil and the nutritional value of the crop are meaningless to them. Is this too harsh a judgment? Look at the nutritional quality of our food and the worn-out state of our farmlands to answer that question

I'd like to insert a rather esoteric opinion here. It is my contention that attempting to turn agriculture into an industrial process breaks a fundamental agreement that mankind has had with nature since the inception of thinking humans on this planet. Not only with nature in general, but with the individual plant and animal families with whom we have these ancient agreements. The agreement with cattle, for instance, is that their human herders will offer protection from wild predators, shelter and warmth when necessary, and provide good food and water to them. We will help protect their offspring, care for them when they are sick or injured, and work to improve the breed. In exchange, the cattle provide for us their milk, meat, hides, manure, and sometimes labor. This has been a fair trade for the animals and for the humans taking on the responsibility.

We humans have long had a similar agreement with members of the plant kingdom: care, protection from competing plants, fertile soil and abundant water, working to improve the breed. Industrial agriculture and corporate greed have broken these agreements, and more than broken them: these ancient pacts have been violated in the most obscene manner. An old English term for a farmer and livestock person was a husbandman. To husband was a verb that meant to care for as a wife's husband would care for their family: To husband the land, and the crops, and the animals. Wise husbandmen passed on a better farm than they inherited, passed this on to their children and to the descendants of the plants and animals they had cared for and partnered with. We who wish to create a new and better world should strive to get back to that ideal, and to extend it to all of the Earth that is in our care.

Getting back to our critique of today's agriculture: Regardless of their intent, neither the granola heads nor the nature nazis have proven to have much of a clue when it comes to the big picture. It's time to change that situation. In order to make a new agriculture, we need to use everything we know or can find out, from any discipline. Being a believer and purist of any one school or philosophy of agriculture, and trying to bend reality to fit those accepted truths, is not going to lead us forward.

Most organic growers have no clue what minerals are in their soil. Is it not so? The chemical growers are generally a little better informed, as they are used to getting their soil tested in order to find out how many pounds of chemical fertilizer to add, but they have little understanding of the essential role of the nutrient minerals either.

Our physical reality is made of minerals, also known as elements. There are 90 or so naturally occurring elements, from Hydrogen to Uranium, and we don't really know how many of them we need in order to live, but it's a lot of them. We must have Iron to transport Oxygen in the blood. Calcium and Phosphorus are used to build the crystal lattice of our bones and teeth. Lack of Zinc causes sterility, decreased brain development, loss of sensory acuteness. When the immune system is threatened by infection it releases its stores of Copper from the liver and pulls Iron from the blood. Many metals are re-used over and over as catalysts in the formation of proteins and amino acids. They serve as templates, shapes, that the proteins are folded around. The shape of the protein determines its fit into its intended destination in a living cell. The health, growth, and reproduction of all living things is dependent on the availability and proper balance of mineral elements.

Despite the pervasive ignorance in agriculture, we all know from our nutritional knowledge that minerals are essential to our health. How many people take a vitamin/mineral supplement? Or Calcium supplements? The science of nutrition is well aware of essential minerals, and nutrition books, radio programs, and websites are always decrying the lack of minerals in our food, telling us how the soil is depleted of minerals, and how we can save ourselves from this menace by taking a mineral supplement. Meanwhile, the organic food promoters keep claiming that organically grown food has more minerals, without having a clue whether that's true or not, and in most cases without having an inkling if there are actually any minerals in the soil at all.

Why the disconnect? If minerals are not in the food it's because they are not available in the soil. So why not add them to the soil and get them in your food? At the same time, feed and activate the soil life, bring the humus level up to optimum for your soil and climate, and provide the energy the plants and soil life need. The soil will be healthy, the plants too, and so will the people and animals who eat the nutrient-dense food grown in the Ideal Soil.

If we look at agricultural soils from a nutritional standpoint, they are much more than an anchor for the roots, a base to keep the crops from falling over. Each crop harvested and taken away depletes the soil's store of essential nutrient minerals. If the minerals are not replaced, we eventually reach a point where there are not enough left to grow a healthy crop with the ability to mature seeds for the next generation. Long before this point is reached, the nutrient density of the crop for human and animal food has suffered. Much of our arable land worldwide is producing empty calories, mostly carbohydrates made from the atmospheric elements Carbon, Hydrogen, and Oxygen. The solution, the only solution (barring the ability of plants or soil organisms to transmute elements alchemically), is to supply these needed minerals from a source where they are abundant. That source should ideally be located as close as possible to where the minerals are needed in order to minimize transportation costs. It makes no sense to ship ground limestone across the country when every state in the USA has limestone deposits, but when it comes to rare elements like Selenium or Boron which are only found in concentrated form a few places in the world, the transport costs are justified.

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.

A wonderful thing about a balanced, mineralized soil based on the soil's exchange capacity is that everything else becomes easier. The soil pH self-adjusts to its optimum, plant disease and insect problems largely disappear, water retention, drainage, soil texture, and rate of decay of organic matter all become self-regulating and automatic, weather permitting. The grower knows that the nutrients are in the

crop because the nutrients are available in the soil. The soil life is active and healthy and helping to make these nutrients available, and the plants growing on this ideal soil have free-choice of any nutrient they want, in balance, a balance designed by intelligent science and observation.

All of this can be achieved using minerals in the form of naturally-occurring rocks and mineral ores or their purified forms, ancient sea-bed deposits, ocean water, and the byproducts from plants and animals. The cultural practices one is presently using may change little, except to become easier. This is real science in harmony with nature, using all of the best of ancient and modern knowledge intelligently: the New Agriculture.

There are a few simple and basic principles that govern soil mineral balance. The most important to understand is the soil's Cation Exchange Capacity, or CEC, often referred to simply as exchange capacity or EC. This is a measure of the quantity of nutrients and non-nutrients the soil can hold, how big its "holding tank" is. The lower the tank gets, the more the soil life and plants have to struggle to get their nutrients. On the other hand, if one applies more nutrients than the soil can hold, those nutrients will wash away in rain or irrigation water, or build up in the soil. Excess nutrients are either unnecessary or harmful. One would not put 30 gallons of gasoline in a twenty gallon tank and expect to gain anything. Exchange Capacity EC is the amount the soil can hold onto and use. One must know their soil's exchange capacity, and its % of saturation by different nutrients, to know where one is now, and where one needs to go. In the next chapter we will gain a working understanding of the soil's cation exchange capacity.

If the songbirds are singing, we are getting close.



From the book

The Ideal Soil 2014

A Handbook for
New Agriculture V2.0

Michael Astera

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