What is the soil uptake form(s) for potassium?

The soil uptake form for potassium is the potassium ion. Plants primarily absorb potassium in this ionic form, which is essential for numerous physiological processes. Potassium plays a vital role in regulating water use in plants, enzyme activation, photosynthesis, and the synthesis of proteins and starch. Its uptake directly influences plant growth and development, making it critical for crop productivity.

The other options presented do not represent forms in which potassium is taken up by plants. Calcium and sulfate ions are important nutrients themselves, with distinct roles in plant physiology but are not related to potassium uptake. Boric acid, while it serves as a micronutrient, also does not correlate with potassium. Understanding that potassium is specifically absorbed as a potassium ion helps clarify its critical role in agricultural practices and soil management.