"Produce should be at the heart of the shopping experience, and onions and carrots are critical to that."
Imperator carrots in its Finest range "are performing strongly", he added, while the giant pink onion Rosanna has featured in its relaunched in-store magazine.
British Onions vice-chairman Chris Wilkinson said: "We shouldn't give up and say you can't innovate in onions."
Grocer editor Adam Leyland emphasised the importance of food in the ongoing battle for retail market share. "With the supermarkets building their convenience store estate, and budget stores increasingly offering food, there is more produce on the high street than ever," he said.