People are being urged to take extra care to avoid starting bushfires during the heat wave, with some farmers saying they have lost crops worth thousands of pounds.
The National Farmers’ Union (NFU) said bushfires are one of the biggest risks facing farmers during the heatwave.
A farmer told the BBC he lost around £40,000 worth of crops when one of his fields went up in flames last week.
England experienced its driest start to the year since 1976.
The UK’s hottest ever temperature was recorded last Tuesday, with thermometers hitting 40.3C in Lincolnshire and more than 30 places reaching temperatures above the previous record.
David Exwood, vice president of the NFU, said that even as the weather turned cooler, the lack of rain had increased the risk of field fires.
“It takes a lot of care when people are out in the open because everything can catch fire in this weather,” he said.
Andy Barr, who owns an 800-acre farm in Lenham, Kent, had a 50-acre field of barley destroyed by a fire last Saturday.
Although he hopes to make an insurance claim, Mr Barr said the crop is worth around £40,000.
He said it was a huge shock to see his hard work go up in flames.
“You spend a year cultivating it and you really like to see the fruits of your labor this season. This was very disappointing,” he said.
“But I’m over the shock now and we just have the slightly worrying times to see what the insurers come up with.”
Mr Barr was also grateful to firefighters and neighbors who helped stop the fire from spreading further by plowing up crops that had not yet been burnt to put out the fire.
Farm insurer NFU Mutual said the majority of farmers had insured their buildings, machinery and crops and said it had seen a “significant increase” in farm fire claims during the heat wave in recent weeks.
Last year it estimated the cost of farm fires to exceed £70 million.
He urged people not to throw away used matches or cigarettes, not to use disposable barbecues on grass or bog and not to litter, as discarded bottles can focus sunlight and start a fire.
The NFU’s David Exwood said the dry, hot weather was also leading to reduced yields and quality of some crops such as potatoes, sugar beet and maize.
He said this could lead to shortages of some products on store shelves in the short term and increased prices for customers.
The longer the dry weather continues, the greater the impact, he added.
On his own farm in Sussex, Mr Exwood said his maize was struggling due to a lack of rain and he expected a “dramatically reduced yield”, which could cost him tens of thousands of pounds.
Hannah Buisman, who works on her parents’ farm near St Albans in Hertfordshire, said they had also seen reduced yields in hay and cereal crops due to the heat.
He said this was hurting the farm financially at a time when costs for things like energy were rising.
Ms Buisman said the family had also put off combining crops last week because she felt it was too risky in the hot weather. If the combinations hit a bottle left in a field or flint it could ignite and start a fire, he explained.
He urged people not to leave waste in the fields, adding that a neighboring farm lost 240 hectares of crops in a fire.
“It’s the worst nightmare, especially in years as volatile as these,” he said.