British crop yields rise despite cut in fertiliser use, research finds
Fertiliser use on key crops down more than a quarter on 2010-19 average, while yields increased 2.4%
Nabiha Ahmed - Fri 28 Jul 2023
Britain’s farmers increased their yields of major crops last year despite significant reductions in fertiliser use, according to research.
Making artificial fertilisers relies on natural gas, the price of which rose sharply last year after Russia’s invasion of Ukraine. Fertiliser prices more than tripled, from £233 a tonne in 2020 to £766 a tonne in 2022, which farmers say led to a reduction in their use.
Data from the Department for Environment, Food and Rural Affairs (Defra) published last week revealed that for key crops – wheat, barley, oilseed rape and sugar beet – fertiliser use decreased by an average of 27% compared with the 2010-19 average. Despite this, yields of those crops were 2.4% above average compared with the same period.
An exception to the trend was the 10% increase in the use of fertilisers in the cultivation of potatoes, with a 8.6% reduction in yield.
Fertiliser use in agriculture is a major cause of pollution. In 2022, Defra found that pressure from agriculture accounted for 40% of pollution in inland water bodies. They estimated that 50% of nitrate pollution, 25% of phosphorus in the water environment and 75% of sediment pollution came from agriculture.
Martin Lines, the chief executive of the Nature Friendly Farming Network (NFFN), a group of farmers who campaign for sustainability in the industry, said the data showed how reduced fertiliser usage “can bring big benefits to the business and beyond”.
While the “alarming” price rises of fertiliser came as a “real shock” to farmers, Lines said, the minimal impact on yield was unsurprising. “We know that a lot of fertiliser applied to fields in the UK is not taken up by the crop, and instead gets washed into rivers and streams.”
David Lord, an arable farmer based in Essex, described the move towards natural fertilisation methods as “definitely driven by economics”. He said he had reduced nitrogen usage by approximately 30% in the last decade, and believed that the recent gas crisis had forced farmers to become more environmentally efficient.
“People are learning that using less fertiliser opens up the opportunity to try more nature-friendly methods,” Lord said. “Artificial fertilisers have a cost to us as growers, but also to the climate.”
Artificial fertilisers can also be detrimental to plants, according to Andrew Mahon, an arable farmer in Bedfordshire. Having reduced his use of artificial nitrogen by 15%, Mahon likened nitrogen fertilisers to “drinking four espressos in the morning. It gets you buzzing, and you get that comedown afterwards. And it leaves plants more prone to disease”.
Although decreased fertiliser use appeared to have little impact on yield in 2022, Lord and Mahon acknowledged that last year’s harvest was an anomaly. Mahon said: “Crops were pretty good last year and there was so much sunlight. That is what drove yield last year.”
“It’s really hard to make a statement from one year,” Lord said. “Plants managed to perform a lot better than they do normally.”
Both Lord and Mahon expressed the importance of using nitrogen for fertilisation. Lord described nitrogen fertiliser as “essential to growing consistent live food” for farmers, but admitted that there was a need to use less of it.
Lord said the “crackdown” on urea by the government had been frustrating for farmers. “Urea is a really important product,” he said. “If we didn’t have it, it would be more harmful for the climate.”
In 2022, the government announced that the use of untreated urea would be restricted from 15 January to the end of March each year.
The move away from artificial fertilisation had led to a return to mixed farming methods among farmers, Lord and Mahon said. This includes livestock farming, which is the best way of cycling nutrients into soil, according to Lord, which he said was one way farmers could “decrease usage [of artificial fertiliser] without actually impacting production”.
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This article was amended on 31 July 2023. A previous version stated that “fertiliser prices almost tripled from £233 a tonne in 2020 to £766 a tonne in 2022”; however, £766 is more than triple £233.