Sulfur (S)
A secondary macronutrient that supports protein synthesis and plays a role in deep green color. Sulfur is also used to lower soil pH in alkaline soils — a valuable use in the West and areas with hard water.
Sulfur is required for amino acid and protein synthesis in grass. It also acidifies the soil, which makes it a dual-purpose amendment in alkaline regions.
Soil pH: Elemental sulfur (granular) acidifies the soil as soil bacteria convert it to sulfuric acid. This is the recommended way to lower pH in lawns (compared to aluminum sulfate, which can be toxic in high amounts).
Fertilizer source: Sulfur-coated urea (SCU) and ammonium sulfate are common sulfur-containing fertilizers.
Deficiency signs: Uniform yellowing of new growth (different from iron/magnesium deficiency, which shows interveinal patterns).
More on Micronutrients
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