Chloride is an essential micronutrient.
Tables 1 and 2 show the most recent research results. Cl Deficiency Symptoms. Most varieties do not show the leaf spotting, but do exhibit consistent yield response when soil Cl levels are low. Potassium chloride or muriate of potash is the most readily available form of Cl-containing fertilizer. Potassium chloride is a dry granular material that can be mixed with dry N materials.