Key facts
- Sulphur enhances nitrogen efficiency and protein availability in grass.
- Light-soiled farms show a better response to sulphur applications.
- Recommended sulphur application is 20kg S/ha/year for grazing and 15kg S/ha for silage.
Sulphur application is crucial for enhancing nitrogen efficiency and protein availability in grass, particularly on light-soiled farms. Recommended rates are 20kg S/ha/year for grazing and 15kg S/ha for silage, potentially reducing nitrogen leaching by 22kg N/ha and increasing grass yield.

Optimizing fertiliser use through sulphur application can lead to significant cost savings for farmers by reducing nitrogen waste and increasing crop yields, thereby improving overall farm profitability and environmental sustainability.
The article emphasizes the importance of sulphur in maximising fertiliser efficiency and boosting grass production. Sulphur plays a significant role in nitrogen (N) utilization, helping farms make the most of both slurry and chemical nitrogen applications. It is also vital for protein availability, as it is a component of two key plant amino acids. Farms with lighter soils are more likely to see a positive response to sulphur applications, although they also face a higher risk of sulphur leaching. Sulphur deficiency can manifest similarly to nitrogen deficiency, causing plants to turn yellowish. The recommended application rate for grazing land is 20kg of S per hectare per year (16 units/acre/year), ideally applied by July and spread after each grazing. For silage fields, following the first cut, an application of 15kg of S per hectare is advised, also after each cut. Data from Johnstown indicates that sulphur application can lead to a grass yield increase of 2.6t/ha, a rise in nitrogen uptake of 38kg/ha, a reduction in N leaching by 22kg N/ha, and an overall improvement in nitrogen use efficiency of 25%. Farmers are advised to choose fertiliser products that contain sulphur alongside nitrogen, phosphorus (P), and potassium (K), such as an 18-6-12 + S blend, depending on their phosphorus needs. The article notes that the challenging start to the season may have prevented some farmers from applying sulphur as planned.