The Real Potato Co is warning that supplies of its Piccolo and Bellini potatoes are shorter than forecast because of the wet summer.

The farmer-owned brand, which is part of Tesco potato supplier Branston, will start to run short of Piccolo in November, according to field director David Nelson.

"There's been an increase in greening, as with most growers, and we've had some waterlogging and a few cases of blight," said Nelson. "We're 10% short of our budgeted crop volume."

Piccolo is a seasonal variety, but even stocks of Bellini potatoes will be exhausted by Christmas, Nelson said. Mediterranean supplies won't be available until March.

The brand was launched exclusively in Tesco stores in May and racked up sales of 1,100 tonnes in the first 16 weeks. There are now plans to widen availability to other retailers. The Real Potato Co is urging consumers to back an online petition declaring the spud the King of Veg.