Why is sulfur used in lawn fertilizer?
The sulfur slowly breaks down (with help from oxygen from the air and water) to produce an acid that lowers the pH of the soil. The lower pH of the soil helps make the iron naturally in the soil more available to the grass as a nutrient. Iron helps provide a deep green color. The soils in the western U.S. have a tendency to have a high pH and benefit from the use of sulfur. An excellent way to introduce sulfur to lawn is to use ‘sulfur-coated urea’ (SCU), which provides sulfur and nitrogen (the nitrogen is from the urea).
