Phosphorus occurs in natural geological deposits. Deposits can be found in the U.S. and other parts of the world. To make the P in phosphate ore soluble and available for plants to use, the ore is combined with sulfuric acid and further processed to make many different kinds of phosphate fertilizers. Potassium protects plants against stresses. Potassium protects plants from cold winter temperatures and helps them to resist invasion by pests such as weeds and insects.
Potassium stops wilting, helps roots stay in one place and assists in transferring food.
Potassium is a regulator. It activates plant enzymes and ensures the plant uses water efficiently. Potassium is also responsible for making sure the food you buy is fresh. The element potassium is seventh in order of abundance in the Earth's crust. Through long-term natural processes K filters into the oceans and seas.