The Necessary Role of Potassium

Potassium (K) deficiencies in both corn and soybean crops have shown up in drought areas this growing season. K is one of the most necessary nutrients for crop growth. Unlike nitrogen and phosphorus, K does not become part of the chemical structure of the plant. Instead, it has the most important job of activating as many as 60 enzymatic and plant hormonal reactions. These regulate the many physiological and biochemical processes of the plant, allowing it to function and grow. Among K’s many important jobs, it regulates the opening and closing of the stomates in the leaves. These pores allow water vapor and gasses through. Where K supplies in the soil are limited, plants suffer. Inadequate K supplies inhibit the plant’s stomate response making plants more susceptible to drought. Soil tests will prove K levels. Where deficiencies are noted, consider applying adequate K in the spring at or before planting. Crops take up most of their K requirements in early vegetative stages (source: Michigan State University).