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Important Soil Nutrients


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All plants need nitrogen, phosphorus, and potassium for growth and development. Commercial synthetic fertilizers attempt to provide these nutrients to plants in different proportions. The system for delivering these nutrients, salts and petroleum based fertilizers, are detrimental to the life in the soil ecosystem, the Soil Food Web, that benefits all plants with their nutritional needs. By nurturing the life in the Soil Food Web and providing nutrients in a natural form that enhance  populations of microorganisms in the soil, all plants can gain the nutrients they need for growth much more  efficiently. This is how the system has evolved. This system relies on the symbiotic relationship between plants and the soil organisms, the soil builders.

Approximately ninety-five percent of most plants  are composed of carbon, hydrogen, and oxygen. Nitrogen, phosphorus, and potassium are not the only nutrients required for plant growth. Other nutrients are necessary for plant growth as well. These micronutrients are needed in lesser amounts but are   as equally important as the macronutrients, NPK. Utilization of the macronutrients by a plant is inhibited by the absents of the micronutrient, leading to false diagnosis of a plant deficiency.

Nitrogen is extremely unstable when it’s in the form needed for plant uptake, and since any nitrogen in this form not utilized by the plant quickly evaporates or is washed away, a slow time release supply is constantly needed. In healthy soil nitrogen-fixing bacteria pull nitrogen from the air, metabolize it and make it readily available to the roots.  In a healthy soil environment with sufficient organic material that supports a thriving, diverse microbial community, Earthworm colonies and other important soil organisms that create a healthy Soil Food Web very little if any nitrogen needs to be added as a soil amendment.

Phosphorus and potassium are also needed in much smaller quantities, if at all and are provided by the organic content of a soil. In a closed system, such as a lawn where the clippings are returned to the soil, this organic matter is constantly being converted by soil organisms to nutrients and made available to the root system. You are building a soil when you leave the grass clippings.

Unfortunately poor plant development is often times attributed to a lack of one of the three macronutrients ,   even when in reality there is so much available to the plant. Either it is locked up in an insoluble form, or the plant lacks the ability to make use of the nutrient. For example, very little phosphorus is needed for flowering, and it is certain critical hormones, such as cytokines and auxins, that allow the plant to utilize the phosphorus.

Many other biological components of a healthy soil environment provide critical support for plants and their root systems. Ectomycorrhiza scrub roots of the food source that would otherwise be available for other unwanted fungi and nematodes. Beneficial organisms in healthy soil out compete harmful organisms  for available food reducing or eliminating their damaging impact on plants. Endomycorrhiza hook inside root membranes and create long chains or networks, pulling in nutrients and moisture from great distances , virtually enlarging  plant root systems. These in turn are supported by other microbiological life, each type of soil organism has a useful role and plays an integral part of the Soil Food Web.

As a cornerstone species Earthworms aid in the distribution and colonization of beneficial microorganisms throughout the soil. All plants on the planet have evolved and depend on the organisms that build sustainable, healthy life supporting soils. Without these tiny beings that make up the Soil Food Web we would not exist.