What is PolysulphateTM?

PolysulphateTM is a unique, multi-nutrient fertiliser containing sulphur, potassium, calcium and magnesium in soluble, readily absorbed forms. It is mined in its natural state from a deposit of polyhalite in the Cleveland Potash Boulby Mine in the UK.

PolysulphateTM contains:

  • 48% SO3 as sulphate
  • 14% K2O as from sulphate of potash
  • 6% MgO as from magnesium sulphate
  • 17% CaO as from calcium sulphate

Polysulphate™ is available as a 2 – 4mm granular product which has excellent spreading characteristics, both when applied as a straight or combined with other fertilisers. PolysulphateTM can be applied either as a straight or formulated by Origin Fertilisers into a wide range of compounds for all crops. It is also certified for organic use.

Visit www.polysulphate.com for further detailed information.

The benefits of PolysulphateTM

PolysulphateTM offers several key agronomic and practical benefits, including:

  • Provides 48% SO3 together with potassium, calcium and magnesium all in the sulphate form which are soluble and readily available for maximum crop uptake
  • Fully soluble with all nutrients available for plant uptake during the growth period
  • Prolonged release of sulphate compared to ammonium sulphate = lower risk of leaching, particularly beneficial at times of high rainfall and for light, sandy soils
  • Source of sulphur that does not contain nitrogen = ideal for legumes
  • 2 – 4mm granular product with excellent spreading characteristics as a straight or in a compound
  • Low chloride = ideal for chloride sensitive crops
  • UK produced fertiliser with a low carbon footprint and fully approved for organic use

Prolonged nutrient release pattern of PolysulphateTM

Of the many features of PolysulphateTM fertiliser, its prolonged nutrient release pattern is the most beneficial in terms of matching nutrient availability with the timing of crop uptake.

Independent research at the University of Nottingham using soil columns showed that all of the sulphate in ammonium sulphate was released within 6 days of application, whereas Polysulphate™ gave a prolonged, steady release of sulphate over a 50 day period.

The prolonged sulphate release pattern of PolysulphateTM is closely matched to the major growth period and sulphur demand of the crop. It also reduces the risk of sulphate leaching, particularly beneficial on lighter, sandy soils or after heavy rainfall events.

The release pattern of PolysulphateTM – providing both immediate and prolonged nutrient availability – means it can be applied as a single early-season dressing or ‘little-and-often’ during the growing season giving farmers maximum flexibility to tailor their sulphur inputs according to soil type, rainfall and crop requirements.

Click here to download a PDF leaflet on the prolonged nutrient release of Polysulphate.

PolysulphateTM in practice


All grass requires sulphur to optimise nitrogen use efficiency and protein formation in a balanced nitrogen to sulphur ratio (N:S) of 12:1, which equates to an N:SO3 ratio of 5:1, i.e. apply 1kg/ha SO3 for every 5kg/ha N applied.

Origin Fertilisers offer a wide range of grassland fertilisers containing PolysulphateTM with the optimum N:S ratio along with P, K and the additional benefit of soluble, readily available calcium and magnesium which are essential for livestock health.

Origin trials comparing NPK + ammonium sulphate with NPK + Polysulphate showed that dry matter yield increased by 0.75 tonnes/ha. Click below for further details.

Click here to download Polysulphate trial results for grass



  • Apply PolysulphateTM within an Origin Fertilisers silage grade for each cut to complement nitrogen uptake and maintain N:S ratio
  • On lighter soils an application at the start of the spring may also be required

Click here to download Polysulphate trial results for lucerne


  • Apply Polysulphate™ within an Origin Fertilisers grazing grade 6 weeks before turnout for an early bite and for each grazing cycle during the season
  • If set-stocked, and especially on lighter soils, apply early at the start of spring

Cereals and oilseeds:

  • Apply to total crop sulphur requirement either as a straight in early spring or in an Origin Fertilisers NS, NPKS or NKS compound during the growing season
  • Readily available, the crop will take it up with the nitrogen over the spring growing period
  • Apply to oilseed rape to optimise yield, protein and oil synthesis
  • Apply to bread-making wheat for yield and to ensure grain protein quality
  • Apply to malting barley for yield and quality

Click here to download a PDF leaflet on wheat fertilisation with Polysulphate

Click here to download a PDF leaflet on oilseed rape fertilisation with Polysulphate

Click here to download Polysulphate trial results for maize



  • Apply in the seedbed or soon after emergence
  • Peas have a sulphur requirement but do not require nitrogen
  • Polysulphate™ provides an option to apply readily available S with zero-N
  • Used by the plant at an early stage to feed the nitrogen-fixation process, which occurs within the root nodules and for protein synthesis in the plant

Click here to download Polysulphate trial results for vining peas

Click here to download Polysulphate trial results for combining peas

Brassica field vegetables:

  • Brassica crops have been shown to be particularly responsive
  • Apply as a base dressing, especially on high-risk light soils

Click here to download Polysulphate trial results for broccoli

Click here to download Polysulphate trial results for cabbage

PolysulphateTM from Origin Fertilisers

Origin Fertilisers can supply PolysulphateTM either as a straight or formulated into a wide range of NS, NPKS, or NKS compounds tailored to all soils and crops.

PolysulphateTM enables Origin Fertilisers to make compounds containing nitrogen (N), phosphate (P), potash (K), sulphur (S), calcium (Ca) and magnesium (Mg) to which we can add micro-nutrients, including: boron (B), cobalt (Co), copper (Cu), iron (Fe), manganese (Mn), selenium (Se) and zinc (Zn).

Prolonged release N and S:

By combining Origin Enhanced-N (OEN)TM and PolysulphateTM together, Origin Fertilisers can produce compound fertilisers with a unique prolonged nutrient release pattern for both N and S to provide a sustained supply of readily available nutrient for crop uptake.

Contact your Origin Fertilisers sales manager for more information on our PolysulphateTM product range, including analyses, crop recommendations and spreader settings.