Polysulphate-powered fertiliser boosts productivity & environmental benefits

New Polysulphate-powered grassland fertiliser delivers productivity and environmental benefits

May 8, 2024
3 mins

A new sustained release multi-nutrient fertiliser designed to boost grassland yields, quality and palatability for dairy, beef and sheep producers is being launched by Origin Fertilisers.


  • Builds on proven benefits of Polysulphate
  • Balanced nutrition for grass and livestock
  • Significant dry matter and crude protein gains seen


Based around ICL Polysulphate, Origin Sweet Poly Power combines seven key nutrients in a balanced formulation with proven benefits in grassland production, says Origin Fertilisers’ Mandy McAulay.

“Sweet Poly Power builds on our existing Poly Power range and adds sodium, a key element of our Sweetgrass grassland blends, to form a high performing fertiliser for all livestock producers with both productivity and environmental benefits.

“At the heart of the product is Polysulphate which contains sulphur, potassium, magnesium and calcium in a prolonged release plant-available form that provides the exact amount of these essential nutrients required by the grass through the growing season.

“The nutrient release has been proven to last for up to 55 days so not only are grass yields maximised, it also reduces potential leaching of key nutrients from the soil.”

Nitrogen and phosphate – where required – are added together with a low hygroscopic, specially coated sodium to increase grass palatability and dry matter intake, she explains.

“The product provides up to seven key nutrients in one application – N and S to drive growth and protein formation, P for root and shoot growth, K to aid water regulation, Mg to support photosynthesis, Ca to improve animal health and Na to improve grass palatability.”Depending on requirements and the results of soil testing, we can fine-tune the formulation to deliver a prescription nutrition solution specifically matched to individual soil and crop nutrient needs.”


Sulphur key to success

According to Richard Ward of ICL, who mine Polysulphate from under the North Sea, the multi-nutrient fertiliser has much to offer grassland producers.

“If you look at sulphur for a start, atmospheric levels have diminished significantly over recent years as industry has become more aware of pollution and the farmyard manures and slurries we are all being encouraged to use more of contain very little.

“Yet we know sulphur is essential in driving N utilisation and building essential crude protein levels in grass. So, if you are not applying sulphur, you won’t be able to get the most out of any of the nitrogen sources you have, including organic ones.

“You’ll probably also have to buy in more inorganic nitrogen to make up the shortfall. With its 48% sulphur content and slow release nature, Polysulphate is the ideal way to ensure you have sufficient sulphur available to use all N as efficiently as possible.

“If you’re going to be relying more on clover and legumes in your grassland in the future, as encouraged by the latest SFI, again Polysulphate is essential in making sure you use all the nitrogen produced by these as effectively as you can.”

Polysulphate also contains Magnesium and Calcium elements with both shown to play a vital role in plant health, root development and growth, he adds.

“From an environmental standpoint, Polysulphate is also the lowest carbon footprint fertiliser produced, being simply mined and crushed without further processing and its prolonged release nature minimises volatilisation and nutrient loss from the soil.”


Proven benefits

Extensive trials have shown this sustained nutrient supply and ability to improve NUE can deliver an increase in grass yields of 29% together with an increase in drymatter of over 10%, Richard Ward points out.

“The additional sulphur provided also significantly improved the protein content of the grass.

“All in all, these improvements lead to denser, heavier, more nutrient-rich forage which, combined with the increased palatability and digestibility from a lift in sugars of over 9%, produces healthier, more productive animals for the same, or less, cost.”

According to Origin Fertilisers technical director Peter Scott, the company’s own trials on Polysulphate have highlighted particular improvements in the all-important crude protein of forage.

“We’ve seen positive trends in terms of forage yield, but it’s in the area of nutritional value and mineral content where we have seen the biggest gains,” he explains.

“In one particular trial we saw a significantly improved N:S ratio in forage which resulted in a 56.3% lift in the amount of sulphur contained in the forage and a corresponding crude protein increase of nearly 7.5%.

“By combining the benefits of Polysulphate with the added palatability from Sweetgrass’ sodium and the protected N and P from our Poly Power range, Sweet Poly Power is a unique fertiliser with significant benefits for grassland producers.”