Arable farmers are facing the threat of soaring fertiliser prices at a time when many are already losing money due to low crop prices. But there are ways to reduce fertiliser use – and therefore costs – without impacting yields, according to speakers at this year’s Cereals Event. 

The carbon border adjustment mechanism, which is due to come in in 2027, will levy a tax on imported fertiliser, adding to already high input costs, said speakers in the BASE-UK carbon tax seminar. “About 50% of our carbon emissions is from nitrogen fertiliser,” said David Aglen, a farm manager in Scotland. “But we’ve found we can cut our use by 40-50kg/ha on wheat crops without affecting output.”

Grass and legume leys in the rotation are a great way of building soil fertility, particularly if you can graze them, while using foliar urea instead of granular ammonium nitrate improves nutrient use efficiencies, he added. In addition, growing heritage wheat varieties or wheat variety blends increases root depth and mass, to scavenge more nutrients from the soil. “There are lots of little things we can do to help.”

Adopting a little-and-often approach to fertiliser applications has helped agronomist Kieran Walsh to increase his clients’ nitrogen use efficiency from about 55% to over 70%. “Timing is crucial,” he said. Front-loading applications to boost early biomass is important, after which foliar applications can be used. “However, little and often does mean more fuel use, so you need to allocate it correctly to ensure real reporting.”

When it comes to net zero targets, it’s vital that calculations also take soil carbon sequestration – and existing trees and hedgerows - into account, said Mr Aglen. And new technologies could also help to produce fertiliser with a lower carbon footprint, added Stephan Haefele, head of soil science at Rothamsted Research. “We can’t grow the crops we need to produce without fertiliser; people need to eat,” he said. But if we could use renewable energy to produce it, that will have a lower impact."

To that end, Re-Genus, in collaboration with Land Energy, said it was preparing to launch a new natural fertiliser designed to offer a practical alternative to synthetic products in the £1.7bn UK fertiliser market. 

The fertiliser is produced in the UK using locally sourced fungi, natural nutrients, and recycled raw materials. After trials to refine the formula, the product has been developed into pellets that are easy to transport and compatible with standard farm equipment, including seed drills, fertiliser spreaders, and drones. 

The pellets act as a fungal inoculant, helping to restore soil biology and improve long-term soil health, said the firm. Compared to synthetic fertilisers, the product can reduce carbon emissions by up to five tonnes per tonne applied. It also helps prevent nutrient runoff, supporting cleaner watercourses. By improving natural nutrient cycling, Re-Genus aims to reduce the need for synthetic fertiliser use on farms across the UK. 

Another new technology which could help farmers to reduce fertiliser use is PES Technologies’ new handheld soil health indicator. Regular soil testing allows farmers to make informed decisions about crop nutrition and their long-term soil health, and this new device is designed to provide both farmers and agronomists with quick, in-field insights into the biological, chemical, and physical condition of soil. Paired with a mobile app, it offers a practical way to assess soil health and inform management decisions. 

The device uses PES Technologies’ proprietary sensor system, built into a compact electronic reader. It enables rapid measurement of key soil health indicators like microbial biomass and organic matter, offering results without the need for lab-based testing. Data is sent directly to the user’s phone or tablet, making it easier to track changes in soil health over time.