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A common question we get asked at AGS regarding our organic fertiliser, Sustane, is “As Sustane is so high in organic, will it reduce my pore space and negatively affect my rootzone drainage?”.

We absolutely understand the reasons why people may think this is the case. Fear not, we are here to explain that it most certainly DOES NOT negatively affect drainage and might even improve it! Don’t take our word for it, have a look at this research that was conducted into the use of Sustane (and other organic/synthetic material) and its impact on saturated hydraulic conductivity (ability of water to move through a soil).

Effects of Organic Fertilizers on the Saturated Hydraulic Conductivity of a USGA Rootzone Start Andrew S. McNitt, Dianne Petrunak, and Thomas Serensits, The Pennsylvania State University, 2006.

To determine if heavy use of natural organic nitrogen sources affects the saturated hydraulic conductivity of a USGA recommended rootzone mix


  • The application of large quantities of the fertilizers used in this study or the ash produced from these fertilizers had no affect on the saturated hydraulic conductivity of a USGA specified rootzone.
  • A significant portion of the ash produced from these organic fertilizers was water soluble or, in the case of and Sustane, sand-sized particles.
  • The traditional method to determine particle size distribution through sedimentation is not an appropriate method to determine the particle size of organic fertilisers or the ash produced from these fertilizers because much of the material is soluble in water.

The full article can be found here, I encourage everyone to read it if you are at all in doubt.

Fantastic news, right? There were a few clear reasons for this outcome regarding Sustane. Firstly, Sustane particles are of a similar size as the sand fraction of a USGA or standard Sports rootzone. Secondly, even when these fertilisers were fully broken down the “ash” that remained had no negative affects on ksat due to its solubility. Finally, and most importantly, the amount of organic material applied, even in heavy use, is no match for the amount of organic matter produced by turfgrass in the same period.

So, now we have cleared that up, think of all the great benefits that come with using Sustane;

  • Biologically Diverse: Sustane has the highest known naturally available nutrient concentration. Pathogen free, microbial diverse turfgrass nutrition.
  • Biologically Stable: Fully composted ensuring no oxygen is taken from the rootzone
  • Nutritionally Sound: Sustane delivers a broad spectrum of nutrients complexed in a very high CEC humic base.
  • Proven to reduce turfgrass disease incidence
  • Low carbon footprint
  • Backed by the most research of any organic fertiliser on in the market!

Speak to your local AGS Technical Team or email us at for more info



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