Growing up on a small farm in central Utah and attending a high school in the middle of nowhere, I learned the integrity of a sentence is made up of 26 letters and punctuation marks. English was my worst subject, but I knew enough to realize if you slowly remove random letters from a sentence, at frst, te sntenc miht stil e readble, bu s mor lters dsapar, it bcoes gibris. Soil is much the same way. It has essential mineral building blocks that plants use. If those are depleted, it destroys the soil’s integrity and affects our health.

Over time with many common farming practices, we start to lose some of those minerals to insolubility, erosion or crop exportation. As with sentences, a soil's integrity can deteriorate as these minerals are depleted, leading to reduced plant health, more pest pressure and overall harvest productivity decline. Minerals, both structural and enzymatic, are fundamental to soil integrity and plant growth, playing vital roles in everything from soil structure to nutrient uptake mechanisms.

Essentials of life: Oxygen, carbon and hydrogen

Ninety-six percent of a plant is composed of three elements: oxygen (O), carbon (C) and hydrogen (H). During photosynthesis, these elements combine to form the plant's lifeblood, where carbon dioxide (CO₂) and water (H₂O), facilitated by sunlight, produce oxygen (O₂) and sugars in the form of glucose (C₆H₁₂O₆). Understanding the composition of plants is crucial in agriculture to grow strong crops. Minerals come in two forms: soluble and insoluble. If all minerals were soluble and plant-available at every given moment, they would all wash away and oceans would be mineral-rich, leaving nothing in the soil, thus disrupting life-sustaining processes.

Luckily, most essential minerals are insoluble in the soil; they need to be released before plants can use them. Plants rely on a vast network of microbes to accomplish this. Microorganisms break down soil, trading nutrients with plants in exchange for glucose. This symbiotic relationship helps both parties thrive. I'll focus more on this in a moment.

Plants primarily obtain C and O from CO₂, which is also mainly produced by microbes through respiration, with a small amount of CO₂ coming from the surrounding air. H atoms come from water and are combined with C and O during photosynthesis to build the plant’s cell walls. A plant with nothing but C, O and H, though, is unhealthy and lacks defense mechanisms and healthy nutrients.

Macronutrients: The basics

Nitrogen (N) is the next most abundant element in cellular structure. It makes up 1.5% of the plant's structure and is a key component in proteins, chlorophyll and nucleic acids. N plays a crucial role in photosynthesis, enzyme activation and the structural components of plant cells, influencing overall growth and development. Maintaining a balanced N supply is important, as both excess and deficiency can adversely affect plant health.

These four elements – O, C, H and N – can all come to plants in gas forms from the atmosphere (free to the farmer) and make up 97.5% of dry plant matter. The last 2.5% is found in soil.

Essential nutrients, including phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg) and sulfur (S), play crucial roles in enhancing crop resilience. Ca fortifies cell structure, Mg aids in enzyme activation and S contributes to chlorophyll synthesis. Balancing these essential nutrients is akin to fortifying the crop's structural integrity, much like letters, commas, periods, sentences and paragraphs make up this article. It can be costly and shortsighted to only focus on NPK, as plants need so many more minerals than these.

Micronutrients: The precision players

In agriculture, the role of micronutrients is often less understood by growers. These micronutrients make up less than 0.5% of the physical plant, but elements such as iron (Fe), manganese (Mn), zinc (Zn), copper (Cu), molybdenum (Mo), cobalt (Co) and boron (B) contribute to enzyme activation, photosynthesis and overall metabolic functions. These are crucial for plants to function properly and protect themselves from pests and diseases.

Though required in small amounts, these trace elements are essential for a crop's overall prosperity. Micronutrient availability also controls the growth speed of a plant and affects the nutrients we obtain from plants. Forgetting them is like trying to make a sentence with just 12 letters.

Soil integrity relies on microbial interactions

Healthy soil teems with microbial life, which plays a pivotal role in nutrient cycling and mineral availability. Soil microbes, including bacteria and fungi, decompose organic matter, releasing nutrients in forms plants can absorb. This microbial activity is crucial for the mineralization process, where organic nutrients are converted into inorganic forms accessible to plants. Mycorrhizal fungi form symbiotic relationships with plant roots, extending their absorption capacity. These fungi increase the surface area for water and nutrient uptake, particularly for P and micronutrients, enhancing plant growth.

Without predators though, bacteria and fungus can become problems. Protozoa and beneficial nematodes are integral parts to soil integrity and are directly responsible for releasing minerals in a plant-available and soluble form. Farmers who utilize microbes and focus more on them than their crops have larger and healthier harvests.

This is why cover crops are becoming a vital part of regenerative farming. These microbes need food and cover year-round. A commercial farm in California utilized cover crops to boost soil microbial activity. The diverse root systems of cover crops provided food for microbes, which in turn increased the availability of essential minerals for the main cash crops. This practice not only improved soil health but also reduced the need for chemical fertilizers, showcasing the synergistic relationship between soil microbes and mineral availability.

Practical application: Soil and microbe testing

For commercial farmers, maintaining soil minerals and microbial balance is critical for optimizing crop yields. Regular soil testing is a valuable tool in assessing soil mineral content and identifying deficiencies. Soil tests provide a snapshot of nutrient levels, pH and organic matter content, guiding farmers in making informed decisions about fertilization and soil management.

Microbial tests offer insights into the soil's biological health. These tests can identify the presence and activity levels of beneficial microbes, helping farmers understand the microbial dynamics in their soil. These tests are becoming more common and offer valuable insights into the plant mineral availability. These tests are a must.

General recommendations for maintaining proper soil integrity

1. Soil amendments: Use amendments such as compost and manure to replenish soil minerals naturally. These materials provide a slow-release source of nutrients, enhance soil structure and proliferate microbial life.
2. Crop rotation and cover cropping: Rotate crops and use cover crops to break pest cycles, improve soil structure and boost microbial diversity. Cover crops, in particular, can prevent soil erosion and enhance nutrient cycling.
3. Integrated nutrient management: Understand which fertilizers and chemicals harm soil microbes and which to use to meet crop nutrient needs while maintaining soil health. This approach ensures immediate nutrient availability and long-term soil fertility.
4. Reduced tillage: Minimize soil disturbance to preserve soil structure and microbial habitats. No-till or reduced-till practices help maintain soil integrity and promote a healthy microbial ecosystem.
5. Regular testing: Conduct regular mineral and microbial tests to monitor soil health and adjust management practices accordingly. These tests provide essential data for making informed decisions about fertilization and soil amendments.

Conclusion

Minerals are essential to soil and plant health, integral to everything from soil structure to enzymatic functions within plants. Structural minerals like Ca and Mg build the framework for healthy plant structures, while enzymatic minerals such as Zn and Fe drive crucial metabolic processes to keep plants healthy. The intricate dance between soil integrity and microbial activity further enhances mineral availability, ensuring plants receive the nutrients they need to thrive naturally and are free to the farmers who utilize them.

For commercial farmers, prioritizing soil integrity through proper mineral management is essential for sustainable and productive agriculture. By regularly testing soil and microbial health, applying appropriate amendments and adopting sustainable practices, farmers can maintain soil integrity and maximize crop yields. As we understand and respect the vital role of minerals and the microbe food chain, we can cultivate healthier, more resilient agricultural systems, ensuring nutrient-rich food and environmental sustainability for future generations.