Packers of potatoes have been "manipulating" the price of Maris Piper, starving growers of much needed revenue, it was claimed this week.
A disgruntled grower of potatoes for packers that supply Sainsbury contacted The Grocer to allege that as farmgate prices of Maris Piper soared by a third this season, demand suddenly dried up.
The Lincolnshire grower, who did not wish to be named, but who said he supplied Sainsbury packers Greenvale AP and QV Foods, claimed that Maris Piper potatoes were available in only 30% of Sainsbury stores.
He said: "Between November and the end of January prices rose from £150/tonne to £200/tonne. It looked as if the price was going to rise further, but what the packers have done is decide not to put them in stores. Now prices have come down to around £150-£160/tonne."
Prices were high because of a shortage of good quality Maris Piper, he said. However, because packers were tied into fixed-price contracts with supermarkets, they had been forced to stop supplying Maris Piper or face heavy losses.
He added: "I was always told that if you grow a commodity then the price is set where demand equals supply. It is disappointing that when Piper prices start to rise the product is simply withdrawn and denied to consumers in an artificial bid to keep free market prices down.
"Growers are starting to feel frustrated at the way the market is being manipulated."
A Sainsbury spokeswoman said Maris Piper stocks were simply making way for Vivaldi, which was now more popular. "Obviously customer demand fluctuates week by week and at the moment customer demand for Sainsbury's own brand Vivaldi potatoes is quite heavily outstripping the demand for Maris Piper potatoes. That is the reason that Vivaldi is more readily available at the moment."