Last spring, fearful the pandemic would cause a shortage of migrant workers to harvest the UK’s fruit and vegetables, the government launched a “Pick for Britain” campaign to attract locals to do the job.

It was a perfect test of whether the economy could wean itself off the use of low-paid migrants, which is desired by many Brexit supporters and the government’s stated aim. This, after all, was the sector that relied on them most: an estimated 99 per cent of the UK’s seasonal agricultural workers in the edible horticulture sector come from the EU. And there were suddenly plenty of unemployed or furloughed Britons in 2020 with time on their hands.

The campaign attracted many applicants but few stuck with it. Pro-Force, one of the UK’s biggest agricultural labour agencies, received 15,000 applications but only managed to place 3 per cent of them on farms. Of those 450, fewer than 4 per cent were still on assignment by the end of the season.

For some, this was proof that locals are lazy. “Why is it that our young people and our workforce are shying away from hard work while Romanians, Lithuanians and Bulgarians, et cetera, seem to cope with it?” asked Derek Thomas, a Conservative MP, in a recent select committee hearing.

This narrative ignores the way the job has transformed over the past 30 years. Angus Davison, chairman of Haygrove, a Herefordshire-based berry growing company, remembers the harvest brought in by students, Welsh miners after the strike and “local ladies from Ledbury” who wanted summer cash. They were paid a piece rate and “the slow ones could just be slow and nobody minded”.

But while piece rates are still common, national minimum wage law now requires farmers to top up the pay of workers who do not earn enough. The minimum wage has ratcheted higher and powerful supermarkets have put pressure on prices while demanding higher quality standards, leading to what the University of Sussex’s Ben Rogaly has called an “intensification” of the job.

“We’re calculating [the pick rate] through the day, so we’re telling people through the day, you’ve got to get faster, you’ve got to hit the target of however many units it is,” Mr Davison told me. “We try and train them, use two hands not one hand, if you move like this rather than that it’s easier, if you set yourself a personal target for the next hour that might help . . . it’s a mental and physical discipline.”

The work is irregular and doesn’t stop at weekends, so migrants usually live on site. Meanwhile the harvest season has expanded from about six weeks to between six and eight months. It is neither a summer job for students nor a permanent job suitable for people with families to support or rent to pay.

Britons aren’t lazy, they’re rational. They will do tough or antisocial jobs if the pay compensates sufficiently, like working on an oil rig. But picking jobs don’t pay a premium compared with working in a shop or café. Migrants are rational too. For them, UK farm work does pay a premium compared with the jobs at home. When the premium shrinks, they stop coming. “We are already seeing numbers dropping from Romania,” the chief executive of a seasonal labour provider explained in 2019. “Because of such strong economies in Romania and Bulgaria, they are keeping their own labour and they are paying them more, so they now earn three-and-a-half to four times the salary when they come to the UK, rather than the five to six times of a few years ago.”

The UK government, while telling farmers they must try harder to attract local workers, has expanded a pilot scheme that issues agricultural work visas to people from poorer countries such as Moldova.

They are skirting around a hard truth: if the government really doesn’t want migrant workers in the fields, pay and conditions will need to be substantially better, and that means higher food prices in the shops. Automation might square the circle eventually but the technology isn’t advanced enough yet. Many fear higher prices would hurt the poor, some of whom are already relying on food donations. But the UK is a rich country, with the lowest food prices in western Europe, according to Eurostat data. The root problem isn’t the price of food, it’s the inadequate floor on people’s incomes, something the government is also loath to address.

The UK government says it wants to curb lower-paid migration to create a “high wage, high-skill, high productivity economy”. It should level with people — and with itself — about the trade-offs that involves.