The UK’s weather patterns and temperatures are changing. Records are routinely being broken for rainfall, heat and days of sunshine, demonstrating that so called ‘extreme’ weather events are a threat to agricultural production. Among the lesser-known concerns is salinisation, the build-up of salt in soil.

“It is a silent and often undiagnosed plant killer. Soil tests are sometimes only taken every five years, but with the weather we have been experiencing recently it would be prudent to take tests at least every year. The drought conditions of 2025 and the prolonged dry conditions in the cereal growing regions of England in 2026 have put soils under a new type of pressure,” says Eurofins Agro specialist Shane Brewer.

He suggests that soil salinisation accelerates during dry conditions as high evaporation rates pull shallow, salt-laden groundwater upward through the soil via capillary action. As water evaporates it leaves concentrated salts behind, which increase soil osmotic pressure, restrict plant water intake, and degrade overall soil structure.

“Some may wonder why a follow-on crop has seen poor growth, or why, on rotation, a crop hasn’t performed as well as it did in the same field a few years ago. The answers are in the soil and, with the weather conditions we are facing now, it will pay to know more about the soil health before planting,” he says.

Parts of the UK have suffered damaging weather extremes in just the last 12 months. The east saw one of its wettest winters which caused soil leaching and suffocation from waterlogging. These same soils have also been baked by the hottest and driest spells the UK has ever experienced, and this process has caused potentially damaging salinisation and sodification.

“It is impossible to diagnose these issues without accurate testing. That is why our most recent Soil Health Indicator test has a new section in the report for salinisation and sodification, to show growers the potential threat it poses to their crops. This, in addition to heavy metal and contaminate analysis, helps to demonstrate the threats that are hidden in the soil,” says Mr Brewer.

The east of England experienced only a fraction of its expected spring rainfall in the spring of 2026. Counties like Cambridgeshire received around a third of the normal rainfall, while areas like Shoeburyness, in Essex, saw just 26 percent of average spring rainfall. The three warmest springs on record have been recorded in 2026, 2025 and 2024 and nine of the 10 warmest springs in England have occurred since 2007.

“We can’t ignore the trend for warmer, drier weather in the UK, but we can understand what impact it is having on our ability to grow certain crops in our soils. Rather than monocropping and constantly seeking magic chemical cures to drops in yield, growers can instead analyse soil to establish its properties and make more informed decisions that can improve soil health, crop selection and yield to provide a more sustainable growing system,” he adds.

With many farms routinely using chemical fertilisers, at the start of each season, the levels of potassium, magnesium and sodium are increased. If these are not absorbed or washed out of the soil, the build-up can be exacerbated by drought.

“The build-up of salt can affect soil pH, reduce calcium levels and, in some cases, leave fields containing up to 25 percent sodium at the clay-humus complex (Na-CEC%). In just one season we can see pH be 0.7 points lower than expected, which will have a significant effect on crop health,” he says.

Long term, the effect of salinisation on soil health will begin to change soil structure. Excess sodium can break down healthy soil, causing clay to disperse. This destroys soil pores, leading to severe crusting, waterlogging, and drastically reduced drainage, leaving soil unsuitable for plant growth and prone to erosion.

“With very warm and dry summers, and contrasting wet winters, we have a challenging combination of weather patterns that are detrimental to soil health. Salinisation is just one marker among many, but understanding it can help decision-making and save growers time and money. Only through regular soil tests, that can identify sodium concentrations, can salinisation be identified and, so, if nothing else, we are urging growers to test more often,” he concludes.