Wholesale prices soar by more than 30% and farmers have to renegotiate with supermarkets

Lettuce is being flown in from the US, and imported from Spain and Poland as soaring temperatures increase demand but hit crops in the UK.

The cargo carrier IAG Cargo said it had flown 30,000 heads of lettuce from Los Angeles to the UK in the past week alone.

Tony Clemence, general manager of the Bristol branch of the wholesaler Total Produce, said the company was having to import about 30% of its iceberg lettuce and 40% of its celery from Spain and Poland when all supplies usually come from the UK at this time of year.

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“We’re not importing from the US but people will look at that because they are committed to a quantity for the supermarkets. Spain is mainly growing for its local markets at this time of year, so there is not enough to go around and some will have to look further afield.”

Wholesale prices have soared by more than 30% as the recent heatwave has exacerbated problems that began when the ‘beast from the east’ period of cold and wet weather in March delayed planting.

“Obviously there is increased demand because of the weather but the problem is more about supply,” Clemence said.

The British Leafy Salads Association said the UK crop of salad leaves was 75% of the usual yield at this time of year, while demand had increased by as much as 40% last week.

High temperatures were affecting all farmers in the group’s major salad-growing areas, from Fife and Lancashire to East Anglia and Sussex.

Other crops, including celery, onions, carrots, broccoli and cauliflower, are also being affected by high temperatures, which stress the plants and halt growth. Some growers have also been hit by the lack of rain.

Tim O’Malley, the managing director of Nationwide Produce, said the group was expecting the onion yield to be down by as much as 30% and that vegetables would be smaller than usual. He said the daily wholesale price for carrots was 140% up on this time last year amid similar problems.

“We had a cold, wet spring, which meant crops were planted late and often in cold and wet soil conditions. So the crops got off to a bad start and now they are suffering not just due to lack of rainfall but also heat. At temperatures above 27°C crops simply stop growing and now is the vital growing period. Irrigating crops is simply keeping them alive at these temperatures – alive but not growing. Crops without irrigation are dying,” he said.

So far, prices in supermarkets, which generally agree a contract price with farmers before the season, are not rising. Tough competition, particularly from the discounters Aldi and Lidl, is helping to limit the impact on shoppers but farmers, wholesalers, restaurants, cafes and smaller stores are likely to be hit by rises.

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O’Malley said farmers were negotiating with supermarkets about increasing prices or changing size and weight specifications as they expect the hot weather to continue.

The difficulties come as supplies of tenderstem broccoli, mange tout and sugar snap peas have been hit by heavy rainfall in Kenya that has destroyed thousands of hectares of crops.

In its newsletter, Total Produce told clients there was “currently no alternative country of origin available” for tenderstem broccoli and that supplies of fine beans, mange tout and sugar snap peas were low and their quality “intermittent”.