The supermarket is encouraging consumers to buy their vegetables at Waitrose because its vegetable prices are 13.5 per cent lower than last year.
Broccoli, it claims, has seen the highest price reduction of more than 20 per cent.
Waitrose senior vegetable buyer Richard Bickerton said: "These lower prices ensure that our customers can still stock up on fresh British vegetables, despite a general rise in food costs."
However, Evans has criticised Waitrose for failing to explain that UK growers were not responsible for last year's high prices.
The higher prices were a result of the majority of the broccoli stocks having to be imported from California.
Ewan said: "It's not telling the whole story. I would not want anyone thinking that UK growers were making any money last year. We had a disastrous year and so broccoli had to be imported from California."
"The extra money consumers were paying was not going to British growers."
He added that, although this year has been better, prices paid to primary producers are still ten per cent lower than the "long-term sustainability level" - and yields are not high.
"Its pretty tight - growers are not making any money," he said.
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