DTE Solution Grade Langbeinite is an organic water-soluble powdered mineral derived from Sulfate of Potash Magnesia. This solution grade product provides a balance ratio of potassium (K), magnesium (Mg) and sulfur (S) in a highly available sulfate form. Designed for efficient delivery and quick uptake, this high performance langbeinite will provide your plants with the tools for optimal growth and maximum performance. A soil or plant tissue analysis or a home soil test is recommended before use, but application can be made without one (see instructions for details). Fine 200 mesh powder that can be used with no clogging issues Neutral in pH and will not affect soil acidity OMRI listed for organic growing Can be used in reservoirs, fertigation, drip irrigation or spray applications Shop All Down to Earth products here .