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 can reduce nitrogen leaching by 22kg N/ha.
- Benefits include increased grass yield and nitrogen uptake.
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.