The new variety, called Boldrewood, has been shown at this year’s Chelsea Flower Show in a collaboration between the university, Sparsholt College in Hampshire and Steve’s Leaves, part of Vitacress Salads Ltd which produces watercress in Hampshire and elsewhere.

“It’s a dwarf watercress, so it develops tiny stems and small leaves, making it bite sized,” said Professor Gail Taylor, whose team developed Boldrewood at the university. “It also has good properties for anti cancer chemicals. We’re currently discussing taking it to market.”

Before that, though, Boldrewood is going through trials at a Dorset farm run by Vitacress, which is evaluating varieties as they emerge from the university’s breeding programme. “This is a naturally dwarf variety and it has high levels of some of the key nutrients,” said Tony Reid, Vitacress’ marketing manager. “The only trouble is that it has a tendency to turn red if it is cold.”

Vitacress is still experimenting on how to grow the variety. “We are not quite there yet,” Mr Reid said. “If turning red is a characteristic of the variety, perhaps that can be part of the marketing message.”

Vitacress is evaluating another two varieties from the university, but has to bulk up the seeds before trails can begin. The nutritional profile of watercress is better than spinach, beetroot or any other vegetable, said Mr Reid. “Some of the watercress varieties – including Boldrewood – produce PTEIC, a cancer fighting, naturally occurring plant chemical which is what makes watercress taste peppery. It also reduces DNA damage from smoking and exercise.”

Steve’s Leaves is named after Dr Steve Rothwell, who works for Vitacress, had the first PhD in watercress and has collaborated with Southampton University, Hull University for exercise research and Reading University on cancer prevention properties.

Pictured: Watercress in Sparsholt College’s Mighty Greens garden at the Chelsea Flower Show. Inset: Some of the wild watercress varieties identified by Southampton University featured in the Mighty Greens garden presented by Sparsholt College in Hampshire at this year’s Chelsea Flower Show. Chef Luke Matthews of Chewton Glen in the New Forest has worked with this new material to produce a salad that plays on the sweeter taste of this wild watercress. The college won a silver medal for Mighty Greens, which was designed and built by a team of eight horticulture students.