Healthy, mineralized soils and healthy plants are the key to protecting your crop
Protecting crops from disease or insects always involves a system. I don’t believe that there is any one silver bullet to protect a crop. Many farmers today rely on new and improved genetics, fungicides, insecticides, biotechnology and herbicides to keep the bugs away while also preventing weeds from taking over. This article isn’t about these methods; it’s about prevention through creating healthy mineralized soils and healthy plants.
What this article is about is my life experiences — not only farming myself but also following farms all over this planet. My family’s farm is organic and was started long enough ago that there were no organic-approved plant protective compounds that I know of. I can honestly say that in our almost 30 years of farming organically, I have never seen an economic loss due to disease or insects, nor have we ever seen a need for those types of products.
When the system works, money spent on plant-protective compounds is money wasted. The problem — “problem” meaning the reason this system isn’t emulated by every farmer — is that this is a system based on balanced mineral ratios and levels, plant diversity, and biology. Research does a poor job of testing systems that may take years to get right; it’s easier to develop and sell products to use when the system fails.
Recently, for example, tar spot was a huge problem on a lot of corn fields here in Wisconsin — our neighbors’ corn was wiped out. We saw very little of it on our farm. The push from agribusiness has been to not only use fungicides more than once during the growing season but also to rely on genetic selection. But those things don’t make either the crop or the soil any healthier.
Now, the method of getting healthy mineralized soils will take time, and it will cost money. The problem most farmers face is that they spend all that money on chemicals or on trying to genetically protect their plants, without ever improving their soils. In fact, many of these products have negative side effects.
I certainly believe there is enough evidence that an improved farming system does work; but how do you get there? I will outline and show evidence of some easy-to-do practices. Is there research supporting all this? Probably not, but it is real.
Calcium and Boron
Let’s start with calcium. Just because your pH is fine and you’re using high-calcium lime does not mean that you have enough calcium getting into the plant. Other nutrients like magnesium and potassium can certainly interfere, and, without biology or acid soils, is the calcium in the soil soluble?
Wisconsin doesn’t naturally have any high-calcium lime or gypsum. When I was first farming, though, I found a source in Iowa that was fine ground, so we could use less, and it had other positive additives like sulfur, silica and potassium that helped offset the trucking costs. At that point in my career I thought that calcium was calcium — I had no idea! The source I found was kiln dust, also known as burnt lime. Yes, you can burn lime as it contains about 12 percent carbon. What we had was fertilizer-grade calcium that was highly soluble; it was calcium oxide. In order to handle it, we hydrated it with water and added more sulfur and boron, as I was taught that boron was needed to get calcium uptake. We called this product BioCal.
Being a dairy nutritionist, I put BioCal on alfalfa, and we really saw the plants change. That is why I call calcium the trucker of all minerals and boron the steering wheel. You do need a good base in the soil to draw from, but these were dairy farmers feeding minerals to cows; they had manures to put on their fields and were using fertilizers. We saw reduced insect pressure, the alfalfa had solid stems, and the cows liked it better, so performance and cow health went up.
Folks promoting the use of refractometers say that if you get the sugar reading above 12, the bugs won’t eat your crop. That wasn’t always true, as refractometers don’t just measure sugars — they also measure soluble carbohydrates. That also means amino acids, but the real change was pectins — hence the solid stems. Good levels of calcium shut off a plant enzyme that breaks down pectins, and pectins are important for solid stems in plants. Elevated Brix levels are showing a mixture of sugars, starches and pectins.
Boron is also needed for sugar/soluble CHO translocation and calcium uptake. We have recently been looking at increasing boron use, as that seems to make more improvements. Boron is a soluble anion and not only leaches but ties up. At our farm we mix it with the compost and add it to our carbon-based fertilizers. Boron does better when hooked to carbon; see Figure 1.
Another area where I saw calcium and boron control disease was in banana production in Australia. Disease was really wiping out the bananas as chemical spraying was done on a regular basis. I was at a meeting there and talked about the effect of calcium and boron and the needed uptake. There happened to be a research scientist in the audience who took my idea and tested it out. Though they also added a biological with the calcium and boron, they no longer needed fungicides.
Sulfur
Now let’s look at a second nutrient: sulfur. I did my graduate work on methionine, a sulfur-containing amino acid. It is said that biting, chewing insects don’t do well on complete proteins, so if your nitrogen is high and sulfur low, you can’t make complete proteins, and you set your crop up for more insect pressure. We test our feeds and aim for an N:S ratio of between 10:1 to 12:1.
Today, with less atmospheric sulfur and more use of nitrogen, the problem is worse than it used to be. Consider using ammonium sulfate for part of your nitrogen (200 lbs/acre works great). Add carbon to N fertilizer in the form of molasses, humates or compost. We use materials coming out of an anerobic digestor from dairy farms as our fertilizer base. Not only does this give us carbon but also lots of bugs’ dead bodies and a biological stimulant.
Nitrogen is a necessary evil — treat it that way by using as little as possible when and where needed. Nitrogen is the only nutrient you can grow; as an organic farm, we grow lots of clovers and add compost with added sulfur.
Trace Elements
The last nutrients I will cover are the trace elements. Trace elements are involved in lots of plant functions but are needed in only small amounts. For example, we believe that extra leaf size is a function of zinc, and that bigger leaves equal more photosynthesis, more sugars, a healthier plant, and higher yields. The squash trial in Figures 2 and 3 is a comparison of a conventional field sprayed with fungicides and an organic field in Canada where the plant was naturally protected via a system of compost, trace elements, and foliar feeds with compost tea.
The corn silage trial shown in Figure 4 was done at the University of Wisconsin as we were testing our organic trace mineral mix. The yields were significantly improved and the plant was healthier, as noted by the color of the corn.
The wheat in Figure 5 demonstrates a comparison of a conventional field, on the right, fed DAP and KCl, and the wheat on the left, which was a biologically balanced crop in the Dakotas with better sources of P and K, along with calcium, sulfur and traces.
To be successful, you first have to believe it’s possible. Just as you yourself have an immune system, nutrition is a big part of crop health. Removing stress is also essential for your crop. You need clean air, clean water, and clean, nutrient-rich foods; so do your crops.
We know what it takes to grow healthy, nutrient-rich crops. Like us, they have an immune system that protects them — you just have to give it a chance to work. And your healthier crops will lead to healthier people. This sense of responsibility makes farming a lot more challenging and fun.
Gary Zimmer is the co-owner of Otter Creek Organic Farm in southcentral Wisconsin and the founder of Midwestern BioAg. He is the author, with his daughter, Leilani, of The Biological Farmer and Advancing Biological Farming
