Potassium (K) is important for the manufacture of plant sugars/carbohydrates, increases the chlorophyll in leaves, regulates the opening and closing of leaf stomata and aids in disease resistance, water uptake and the ripening process.  It activates at lest sixty enzymes involved in plant growth!

role in growth

  • "Potassium is the soil cation required in the largest amount by plants, regardless of nutrient management philosophy" (HortTechnology).
  • "Potassium is involved in many plant physiological reactions, including osmoregulation, protein synthesis, enzyme activation, and photosynthate translocation" (HortTechnology).
  • An adequate amount of Potassium in soil stabilizes pH levels for optimal enzyme reactions [by balancing the charge of soluble and insoluble anions]. A great number of enzymes rely solely on the substantial presence of Potassium.
  • Potassium regulates the opening and closing of the stomata which plays a major role in CO2 fixation. With increased CO2 regulation, the rate of photosynthesis increases in correlation with increased chlorophyll molecules.
  • Potassium is directly related to the translation process, including the binding of tRNA to ribosomes.
  • Potassium ions act directly as solutes, contributing to the osmotic potential of cells and tissues.
  • Potassium stimulates gibberellic acid (GA), resulting in stem elongation
  • Potassium can greatly increase the resistance against biotic and abiotic stresses.
  • Photosynthesis is strongly reduced in K deficient leaves. (H. Marschner, 2012)
  • After N, K is the nutrient required in the largest amounts by plants. (H. Marschner, 2012)

How Potassium works to increase crop yields

  • Increases root growth and improves drought resistance
  • Activates many enzyme systems
  • Maintains turgor; reduces water loss and wilting
  • Aids in photosynthesis and food formation
  • Reduces respiration, preventing energy losses
  • Enhances translocation of sugars and starch
  • Produces grain rich in starch
  • Increases protein content of plants
  • Builds cellulose and reduces lodging
  • Helps retard crop diseases


sources of potassium

Selected References