Rock Phosphate Origin


  • Also called “soft rock phosphate”
  • In North America, typically found in the Rockies or southern US
  • Formed by the upwelling of phosphate rich marine waters which are precipitated by organisms leading to sedimentary deposits in a lagoonal (restricted) environment
  • Sedimentary phosphate typically contains high levels of total and available phosphate
  • Usually contains relatively high levels of calcium and silica which are great for soil and plant health
  • Contains low levels of impurities and some trace minerals


  • Also called “hard rock phosphate”
  • In North America, primary sourced in Eastern Canada
  • Removed from stocks or sills, formed by rare alkaline carbonatite complex rock deposits
  • Typically contains lower levels of total and available phosphate compared to sedimentary phosphate
  • May contain high levels of iron, radionuclides and heavy metals



Commercial phosphates (inorganic fertilizers) are developed through the process of crushing, screening and adding sulphuric acid to rock phosphate to form phosphoric acid. Phosphoric acid is then combined with other agents to form the fertilizer. Two common examples are Mono-ammonium Phosphate (MAP) and Di-ammonium Phosphate (DAP) which is processed by combining phosphoric acid with ammonia to form a slurry which is then solidified into a granule.

Although the phosphate found in inorganic fertilizer is readily available prior to application, this phosphate can be quickly lost through leaching and/or reformed into water insoluble phosphate compounds prior to plant uptake.  Inorganic phosphates are also high in salts, increasing soil salinity issues.


Fertoz-Phosphate is a source of high-quality sedimentary rock phosphate mined in British Columbia, Alberta and Montana. High quality sedimentary rock phosphate when used on acidic soils or combined with other amendments and/or biologicals on high pH soils can be as effective as or more effective than commercial fertilizers. Plus, they offer extended phosphorus availability, less leaching, are low in salts and are naturally sourced and formed without extensive industrial processing.

Organic phosphate fertilizers are slower release and less susceptible to leaching. Naturally sourced, organic phosphate fertilizers create a more soil friendly microbe environment which improves the overall soil health, structure, water retention capability and productivity. Organic fertilizers are less concentrated so don’t damage plants through over-application.

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