News & Advice

Sulphur continues to play a critical role in supporting pasture and crop growth across New Zealand’s farming systems, particularly in the key spring growth period when demand for plant-available nutrients rises. 

For Ravensdown, this reinforces the importance of providing farmers with fertiliser options that align nutrient form with seasonal need, helping lift pasture response and support on-farm performance. 

Chief Science Officer Mike White says after winter, plant-available sulphur is often in short supply. 

“Wet conditions can increase leaching losses, while cooler soils slow the microbial activity needed to convert organic and elemental sulphur into sulphate, the form plants can absorb directly,” he says. 

That makes readily available sulphate-sulphur particularly important in early spring, when farmers are seeking to drive pasture growth and maximise the return on fertiliser applications, particularly nitrogen fertiliser. 

Mikes notes that “applying the right nutrient in the right form can materially influence dry matter response, nitrogen use efficiency and overall feed supply. This is especially relevant in an environment where farm businesses are balancing seasonal variability, input costs and the need to make every fertiliser dollar work harder. Matching sulphur form to farm conditions helps improve both agronomic effectiveness and decision-making confidence”.

Mike White, Ravensdown Chief Science Officer

The key consideration is not simply applying more nutrient but applying the most appropriate form to meet immediate and longer-term pasture requirements. 

Sulphate sulphur is soluble and immediately available to plants. In clover-based pastoral systems, that matters because sulphur supports vigorous clover growth, underpins nitrogen fixation and contributes to pasture quality. Strong clover performance is central to productive grazing systems, making sulphate-sulphur an important tool for delivering timely seasonal response. 

Elemental sulphur, by contrast, plays a complementary role as a non-water soluble slower-release sulphur source. It must first be oxidised by soil microbes before becoming plant-available, so supply is delayed and is less vulnerable to leaching losses when still in elemental form. 

Mike said, “This makes it valuable in fertiliser strategies designed to support longer-term sulphur supply, depending on soil type, rainfall pattern and timing of application. 

“For shareholders, the ongoing relevance of sulphur highlights the enduring value of Ravensdown’s locally relevant product range and science-led advice. By helping farmers make better nutrient decisions for their grazing systems, Ravensdown supports pasture and crop performance, on-farm resilience and the long-term productivity of New Zealand agriculture.”