Phosphorous is critical for a wide variety of functions, but it is especially important for the development and growth of roots. Without strong, well-developed roots, yield can suffer. Phosphorous is also important for shoot density, seed maturation, and good plant establishment. Phosphorous is most important in the vegetative and early-bloom phases.

Phosphorous deficiency can lead to stunted growth, smaller leaves, and reduced yield. It can be exacerbated by over-saturation of nutrients in the soil.

Meeting your plant’s phosphorous needs can be a challenge for several reasons:

  • Phosphorous is immobile in soil – it stays where you put it.  Consequently, it’s important to ensure that phosphorous reaches your plants roots at the right time.
  • Phosphorous is only absorbed by the plant in the orthophosphate form. Most phosphorous-containing fertilizers contain polyphosphates, which contain chains of several phosphate molecules. In order for the plant to absorb the phosphorous of a polyphosphate, it must first break the chains down into single phosphorous molecules, called orthophosphate.
  • Phosphates are highly prone to reacting with other elements in the soil, especially the calcium found in hard water. This is referred to as “tie-up.” When a phosphorous molecule is tied up, it is not available to provide nutrition to the plant.  Additionally, these tied-up compounds can clog emitters, which leads to the need for time-consuming acid flushes.

Key Grow Solutions’ products are soluble in water, which allows them to be delivered right to the roots of your plant, no matter what growing system you use. 

Key Grow Solutions’ nutrient line is based on the highly-absorbable orthophosphate form of phosphorous.. Many other fertilizers on the market contain phosphorous in the polyphosphate form. In order for the plant to absorb the phosphorous, though, it needs to be broken down into orthophosphate. KGS’s phosphorous products are ready to be absorbed in the plant, because the phosphorous is in the highly-absorbable orthophosphate form.

Key Grow Solutions also offers a vegetative-stage phosphorous-containing nutrient product that can be used in hydroponic and drip irrigation systems with fewer phosphate tie-up concerns. KGS’s unique polyamine technology can reduce phosphate tie-up, which can lessen the need for acid flushing while helping to ensure that phosphorous is available for absorption by your plants.

Phosphorous can be found in two KGS products: White Royal for your plant’s vegetative stage and Blue Butterfly* for your micronutrient needs.


* Blue Butterfly contains boron, which, at high levels, can cause plant toxicity. It should not be used on seeds.