One of New Zealand's Leading Soil Scientists, Dr Gordon Rajendram, Calls For More Essential Research on Nitrogen Before We Make Bigger Decisions

Nitrogen has become one of the most talked-about topics in New Zealand agriculture. It sits at the centre of conversations about productivity, water quality, environmental regulation, and farm profitability. Yet despite its importance, I believe we are still not investing enough in the research needed to fully understand how nitrogen behaves in our farming systems. For many years, I have worked in soil fertility and agronomy, and one thing has become increasingly clear to me: there are still significant gaps in our knowledge. The science around nitrogen is complex because it changes depending on soil type, climate, rainfall, irrigation, crop choice, and farming practice. There is no single answer that works for every farm. One of the biggest reasons we are not seeing enough nitrogen research is cost. Well-designed field trials are expensive to establish and maintain. Government research is no longer funding projects like they did before the 1990’s, as field trials cost 100’s of thousands to millions of dollars. The costs go up even higher if animals are involved as part of the trial. They require multiple sites, regular soil and plant testing, data collection over several seasons, and careful statistical analysis. Funding is often directed towards projects with shorter-term outcomes or other areas of agricultural research, leaving long-term nitrogen work under-resourced. That is concerning because nitrogen is too important to rely on assumptions, overseas data or modelling alone. New Zealand's soils and farming conditions are unique, and we need research that reflects our own environment. This is exactly why I continue to carry out nitrogen trials. My focus is on understanding how nitrogen moves through the soil, how much is actually available to plants, and how different management practices influence both production and environmental outcomes. Rather than simply applying more nitrogen, I want to understand how we can apply it better. Good nitrogen management is not about using the highest application rate. It is about matching nitrogen supply with crop demand, so plants use more of what is applied and less is lost through leaching or volatilisation. Small improvements in efficiency can benefit both farmers and the environment. The results from ongoing trials are helping build a clearer picture of how different fertiliser strategies perform under real New Zealand conditions. This information is valuable because it gives farmers practical evidence they can use when making decisions, rather than relying on theory alone. I believe New Zealand needs a renewed commitment to independent, long-term nitrogen research. Farmers deserve recommendations based on robust local science, not assumptions or one-size-fits-all solutions. Nitrogen will continue to play an essential role in food production. Our challenge is to understand it better, manage it more precisely, and invest in the research that helps us make informed decisions for the future of New Zealand agriculture.   For more information, please contact: Dr Gordon Rajendram <a href="tel:021466077">021 466077</a> <a href="mailto:rajendram@xtra.co.nz">rajendram@xtra.co.nz</a> <a href="http://www.gordonrajendramsoilscientist.co.nz">www.gordonrajendramsoilscientist.co.nz</a> Contact Media PA <a href="mailto:phillip@mediapa.co.nz">phillip@mediapa.co.nz</a> <a href="tel:0274587724">027 458 7724</a>