Having so much of the crop going to a relatively minor supermarket causes Allan Stevenson few qualms.

Waitrose customers tend to fall into an older bracket – one which seems set to grow as the overall population ages, he explains.

Of more concern is the steadily shrinking UK area.

“I’m worried that if it goes on declining year by year we’ll lose the critical mass needed to justify our supporting industries.

“We could lose firms making specialist equipment and manufacturers will stop registering new potato chemicals.”