Formula: (NH₄)₂SO₄ — 21% nitrogen, 24% sulfur Nitrogen form: Ammonium-N, fast-release and immediately plant-available after watering in Best for: Lawns, blueberries, acid-loving plants, high-pH soils, and crops needing fast green-up Lawn application rate: 5 lbs per 1,000 sq ft (delivers 1 lb N per 1,000 sq ft) Effect duration: Typically 4–6 weeks per application Soil pH effect: Gradually lowers pH over time — monitor annually if used repeatedly Ammonium sulfate is one of the
