Manganese Sulfate Fertilizer is a high-purity manganese sulfate monohydrate (MnSO₄·H₂O) micronutrient supplying 31% elemental manganese and 18% sulfur — one of the most concentrated, fully water-soluble manganese sources available for preventing and correcting manganese deficiency.
Manganese is an essential micronutrient: it sits at the center of the water-splitting complex in photosynthesis and acts as a cofactor for more than 30 plant enzymes involved in nitrogen metabolism, carbohydrate transport, and chlorophyll function. Because manganese is immobile in the plant, deficiency shows first on the youngest leaves as interveinal chlorosis — and it is common in high-pH, calcareous, sandy, or over-limed soils where manganese availability drops sharply. This product is widely used on palms, citrus and fruit trees, vegetables, berries, field crops, turfgrass, and hydroponic systems, and dissolves cleanly for soil, fertigation, and foliar application.
Confirm need with a soil or tissue test before applying — manganese sulfate works best in acidic to neutral soils, while above roughly pH 7.5 a chelated form performs better. Do not tank-mix with glyphosate; apply the two at least three days apart. Wear eye protection and minimize dust when handling, and store sealed and dry.
CDFA registered and third-party lab tested for heavy metals, with results consistently well below required limits. The 50 lb size is repackaged from OMRI Listed® material; other sizes are CDFA registered but not repackaged from OMRI Listed® material.