From Agronomists of the
Potash & Phosphate Institute
655 Engineering Drive, Suite 110
Norcross, Georgia 30092-2837
Phone (770) 447-0335

Spring 2006, No. 3


Fertilizer potassium is sometimes called “potash”, a term that comes from an early production technique where potassium was leached from wood ashes and concentrated by evaporating the leachate in large iron pots (“pot-ash”). Clearly, this practice is no longer practical and is not environmentally sustainable. In food production, potassium is removed from the soil in harvested crops and must be replaced in order to maintain future crop growth.

Over 350 million years ago, the huge Devonian Sea was slowly drying up in the area of Central Canada and northern U.S., leaving behind concentrated salts and minerals. This process continues today in places such as the Great Salt Lake and the Dead Sea.

These ancient marine salts are now recovered and used in a variety of useful ways, with the majority being used as potassium fertilizer. Potassium is a natural plant food because fertilizers such as potassium chloride, potassium sulfate, and potassium nitrate are widely found in nature. Fortunately, there are huge reserves of potash in the earth that can meet our need for this nutrient for many centuries to come. This fertilizer is clearly not an artificial or manufactured chemical, since it comes directly from the earth and is simply recycled through very long geological processes.

Potassium is essential for plant health and there must be an adequate supply in the soil to maintain good growth. When the potassium supply is limited, plants have reduced yields, poor quality, utilize water less efficiently, and are more susceptible to pest and disease damage.

Potassium fertilizers are safe to use since they pose no harmful environmental or health effects. However, like any substance, when used in excess quantities they can have undesirable effects. High-yielding crops remove large amounts of potassium in the harvested portion…amounts that eventually must be replaced for the soil to remain productive.

Potassium is an important mineral required for human health. Since potassium is not stored in the body, it is necessary to continually replace this nutrient on a regular basis with potassium-rich foods. Diets high in potassium and low in sodium have been shown to be beneficial for avoiding high blood pressure.

“Potash” fertilizer comes from many common earth minerals and provides an important boost for maintaining the health of both humans and plants. There are many excellent sources of potassium that can be used to sustain a productive and healthy ecosystem.

For more information, contact Dr. Robert L. Mikkelsen, Western Director, PPI, 617 Oeste Drive, Davis, CA 95616. Phone: (530) 758-4237. E-mail:

Spring 2006-3 AB.pdf

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