what is potassium used for in a plant
1 In Photosynthesis, potassium regulates the opening and closing of stomata, and therefore regulates CO2 uptake. 2  Potassium triggers activation of enzymes and is essential for production of Adenosine Triphosphate (ATP). 3  ATP is an important energy source for many chemical processes taking place in plant issues. Protein and starch synthesis in plants require potassium as well. 2  Potassium is essential at almost every step of the protein synthesis. 3  In starch synthesis, the enzyme responsible for the process is activated by potassium.