Crops will always experience drought, flood, frost, extreme heat, disease, insects and weeds. Healthier crops have better odds of surviving these attacks, while simultaneously slowing the effects of climate change.
That may sound good, but how do you go about raising healthier crops? According to plant health guru Graeme Sait, your crop has better odds of thriving under adverse conditions if plants are functioning at their highest levels. He says healthier plants require available nutrition above and beyond their conventional diet of nitrogen, phosphorus and potassium.
That concept is the basis of what Sait calls nutrition farming. He says that although soil contains 74 minerals, modern farming has evolved to an unnatural balance with too much dependence on the big three. In nutrition farming seminars that he conducts around the globe, Sait tells farmers that better soil biology is needed to make those soil-bound nutrients available to the crop.
Farmers who attend his seminars are taught to focus their attention on minerals, humus and microbes that digest minerals from the soil and release them as plant available resources.
During his Nov. 26 seminar in Winnipeg, The Western Producer sat down with Sait to delve into the concept of nutrition farming.
WP: Why do you say humus is so important?
Sait: When we talk about this concept of nutrition farming, all we’re talking about is minerals, micro-organisms and humus, or some people call it organic matter. Humus is the most important of these three factors because it’s the storehouse for all minerals and the home-base for all micro-organisms. The level of humus in your soil determines the nutritional value of the food you grow. Higher humus levels give you higher nutritional value in the crop.
More importantly, the role of humus has become huge because it’s the single biggest factor in climate change. We’ve lost two-thirds of the humus from our (agricultural) soils. That carbon doesn’t simply disappear. It’s part of the carbon cycle. It’s up in the atmosphere, thickening the blanket and trapping the heat.
In our current agricultural model, we lose humus. If instead we can build organic matter in the way we farm, we would be directly sequestering carbon molecules in the soil. We can’t build or destroy carbon molecules. These are the same carbon molecules that have been on Earth since the beginning of time. But we can put them back in the soil with our farming practices. Farmers can reverse global warming.
WP: Why does calcium play a special role in all this?
Sait: We think of calcium as the trap of all minerals. Every mineral affects the uptake, negatively or positively, of some other minerals. But calcium has the greatest impact because it governs the uptake of seven other minerals. If you don’t have enough calcium, your plant doesn’t get enough of those seven essential minerals that drive immunity and drive resilience and drive production potential. If you’ve over-done it and you have more calcium than your soil can handle, then it will shut down the uptake of those essential minerals and your plants will suffer.
So calcium is this double-edged sword. How do we get it right? There’s calcium in our own bodies and the bodies of other animals and plants. We have a membrane that serves as a gate through which nutrition moves. Calcium is like the guardsman standing at the gate controlling what comes in and out. That’s the role of calcium from the smallest micro-organism up to the largest animal or person. You have to get your calcium right before you think about the other minerals.
In soils, it depends on how much clay you have. The cation exchange capacity (CEC) is the percentage of clay in the soil. If you’ve got a sandy soil, you might have a CEC of three or four or five or whatever. That number tells you exactly how much calcium you need to add. It might be one ton or two tons. But if you put on three tons, you’ve screwed up your soil. A heavy clay might need seven tons, but not all at once, of course. A good soil test will tell you what you need to add.
(Cation-exchange capacity tells how many cations can be retained on a soil particle. Negative charges on soil particles bind positively charged molecules and allow the exchange with other positively charged particles in the surrounding soil water, thus altering soil chemistry. CEC measures soil fertility by indicating the capacity of soil to retain nutrients in plant-available form.)
WP: Why don’t we utilize the 74 soil minerals impacting plant health?
Sait: We’ve been ignoring soil’s available mineral wealth. The definition of the word “science” in Webster’s dictionary is, “adherence to natural laws and principles.” What we should have done is learned from laws and principles of nature. What we’ve done instead is incredibly arrogant. We thought we could do better than the perfection in nature’s blueprint. And now we’re down on our knees staring into the abyss we’ve created by our arrogance.
What we’re starting to realize is there’s a vast collection of minerals in the soil, and they all have a role. Now lately we’ve started looking at three very rare earth minerals, very obscure minerals that have a tremendous impact on seed germination and kick-starting a robust young plant, and promote plant resilience through the season. Scientists are working with silica, cobalt and molybdenum.
Research shows that plants can have a tremendously robust immunity system and tremendous resilience with the proper trace minerals. There’s now a whole field of science in plant immunology based mainly on trace minerals, which we have neglected until now.
Molybdenum governs whether or not a farmer can access the 74,000 tons of nitrogen gas hovering above every hectare of his farmland. If we had access to that gas, it would help balance two forms of nitrogen in the plant: ammonium and nitrate nitrogen. That ratio should be three parts ammonium to one part nitrate. But you’ll never achieve this ratio until you get a significant part of ammonium for free. And you will never achieve free ammonium until you get a minimum of 0.5 parts per million molybdinum. That’s because the enzymes that pull the gas and turn it into ammonium nitrogen in the soil is made from molybdinum. Molybdinum is the key to free nitrogen.
WP: You say soil is mankind’s most valuable commodity, yet some of your clients use what they call smart tillage. Please explain.
Sait: The massive loss of soil every year jeopardizes the very existence of the human race. It all comes back to that substance called humus. Every time you work a soil, you open it up and oxidize some of that organic matter, some of that humus, some of that carbon. And that’s the whole argument in favour of zero-till farming. If you cultivate when the soil is wet, you quadruple the humus loss. Wet open soil accelerates the humus oxidation tremendously.
No-till has a lot going for it, but minimum till with cover crops probably has more value. But a lot of people miss out on that value because they poison off their cover crop. That’s a really bad strategy because you lose the three main components you’re trying to put into the soil, those being carbon, sulfur and nitrogen. You need them in the carbon cycle, the sulfur cycle and the nitrogen cycle. When you desiccate that cover crop with a herbicide, a lot of that goes straight up into the atmosphere. But if you lightly incorporate that cover crop into the A-horizon or the top three inches, and get some soil on it, then the microbes get to work, then you put carbon and sulfur and nitrogen back into your soil.
WP: Does all this mean you’re promoting organic farming?
Sait: No. That could be the final outcome for some farmers, but that’s a business decision, a financial decision. No, the nutrition farming approach is a middle-ground, more of a functional hybrid method of growing crops. With the nutrition farming concept, you can take any technology from anywhere you like. The only criteria is whether or not nature approves of it. If you find you’re working with the natural systems, you’ll find you reduce your chemical dependence. At that point you’ll have very few hurdles to jump if you should decide to go organic.
WP: But moving into full organic usually leads to severe soil erosion, does it not?
Sait: It is an obvious problem in relation to weed management. We talk about it a little bit in this course. There are methods to help combat weeds, one of which is surface cultivation shortly after the crop is planted. At that point the first plants to emerge will be the weeds. So you run a light cultivation that just scuffs the surface, the top quarter inch, to kill that first flush of weeds. I’ve got a grower in Australia using an old rod weeder for that. Then when your crop pops up, the plants emit an auxin hormone that gives them a zone of protection around them that prevents weeds or other plants from invading their space for 24 to 48 hours after emergence.
(Sait owns a company in Australia called Nutri-Tech Solutions. He has developed nine plant nutrient products that are biologically based and certified organic. The products are sold in Canada through Agriculture Solutions in Sebringville, Ont.)