What is the most common form of potassium fertilizer?

The most common form of potassium fertilizer is potassium chloride, often abbreviated as KCl. This compound is favored for its high potassium content—about 60% potassium by weight—and its affordability, which makes it widely accessible to farmers. Given that potassium is a crucial nutrient for plant growth and development, KCl is frequently used to replenish soil potassium levels, ensuring that crops receive the necessary nutrients for healthy development and optimal yields.

Potassium chloride also dissolves readily in water, making it an effective option for various application methods, including top-dressing and incorporation into soils. While the other forms of potassium fertilizers, like potassium sulfate (K2SO4) and potassium nitrate, serve specific roles in certain situations—such as providing sulfur or nitrogen alongside potassium—they are generally used less frequently in large-scale applications when compared to potassium chloride. K2CO3, although it provides potassium as well, is not as common due to its higher cost and lower potassium concentration relative to KCl. Thus, KCl is the standard choice for most potassium fertilization needs in agronomy.