UK maize harvests began three weeks early in parts of the South amid severe drought and record heat, with farmers now facing reduced yields, rising costs, and increased crop disease risks.

Maize crops across the UK are showing marked variability this year, with especially poor performance on less favourable ground.

The situation has become increasingly challenging for growers as extreme weather takes its toll.

See also: Hottest summer pushes UK farmers to brink

Maize Growers Association technical lead Jon Myhill said: “Maize harvest has started everywhere in the country now, this ahead of normal harvest we have experienced in the past.

“It’s been a really mixed bag across the UK, there will be farms that will be 20-30% down on yield this year and then others that are just about running on average.” 

This is echoed by John Thomas, regional business manager for the South East, Wiltshire and West Midlands at Lallemand Animal Nutrition.

“Exceptionally early maize harvests kicked off last weekend in Berkshire, Gloucestershire and Wiltshire, these are likely to be the first maize harvests in the UK,” he said.

Hottest summer – Met Office

The early start in late August, three weeks ahead of the usual cutting date, comes after the Met Office has since confirmed 2025 as the hottest UK summer on record since 1884.

The mean temperature reached 16.1C, surpassing the previous high from 2018. England also experienced one of the driest springs in over a century.

Mr Thomas noted that while early summer warmth and sunshine sped up cob development and starch levels, the overall impact on yields has been negative.

“Yields in this region are generally below average, with poor growing conditions due to the severe drought and several instances of corn borer damage,” he said.

However, the Midlands has fared somewhat better.

He added: “In my experience, some crops appear better on the headland, but are actually much poorer in the centre of the fields.”

While many crops are currently free of eyespot infection, smut has been observed, and corn borer has re-emerged on new farms near Tewkesbury, in Gloucestershire.

Financial challenges

Some farmers now face major financial challenges.

“Some farmers are in a situation where they need to spend £50k on maize because it didn’t rain enough, and that’s without the grass silage that also needs buying in,” Mr Thomas warned.

He advised that, to reduce pest pressure next year, “careful stubble management, crop rotations and a bit of luck and a hard winter” would be key.

He also stressed the importance of condition-specific maize inoculants to control yeasts and moulds, especially given the higher ambient temperatures during harvest, which increase the risk of clamp spoilage.

Forage rye opportunities

Despite the hot weather and dry spring, Neil Groom, manager at Grainseed, said:

“It’s a great opportunity to sow rye grasses and forage rye after the maize as the fields are cleared earlier and the moisture is good.

“I think everyone has had some rain now which is good to see so, we have ideal conditions at the moment after the turn in weather.”

He added: “Due to spring temperatures, a lot of maize was planted early – even in the last few days of March – so that has allowed the crop to establish quicker and get more leaf area faster, so it has had more photosynthesis over the summer.

“It has meant harvest has been about three weeks earlier, which has surprised a lot of people.

“In all regions of the UK now, there are plenty of fields of maize that are ready and can be used for other crops.”