Liquid 100% Ortho 9-18-9-1S Fertilizer
Our 9-18-9-1S is a high-purity liquid plant food manufactured entirely from high-grade, 100% ortho white phosphoric acid (arsenic free), potassium hydroxide, ammonium hydroxide, ammonium thiosulfate, and low-biuret urea. One of the most established formulations in our lineup, it delivers a balanced NPK ratio with a higher nitrogen concentration than our 6-24-6-1S — making it the right choice when crop conditions or soil tests call for more nitrogen alongside phosphorus and potassium.
The 100% orthophosphate source ensures phosphorus is immediately plant-available with no conversion required, while the addition of sulfur supports protein synthesis and overall crop development. Low-biuret urea provides a high-quality nitrogen source with minimal risk of seedling damage.
Its high-purity formulation and low salt index make it suitable for in-furrow, starter, and foliar applications. Clear and water-white in appearance, it mixes cleanly without residue or equipment issues.
