In 1920s Britain it was a popular fast food and often the only green veg available to help protect the nation from winter colds and flu.
But watercress has fallen out of favour among young people and is seen as a dowdy alternative to its trendy rivals kale and spinach.
Just five per cent of under 28s now buy watercress, compared to 41 per cent of 35 to 54 year olds, Kantar Worldpanel data shows.
Growers, alarmed that teenagers and young professionals are snubbing their produce, have decided to fight back with an image makeover for the leafy green.
A new Instagram campaign taglined #watercresschallenge is urging young people to "chop it, blitz it, toss it and wear it."
Tempting watercress recipes include a James Bond-style cocktail good for hangovers, a vibrant green "power ball"; energy snack instead of a caffeine kick at work, and for those still wary about eating the veg a suggestion to use it on the face as a beauty aide.
Devised by the Agriculture and Horticulture Development Board and the Watercress Association, which represents a group of ten commercial growers, the aim is to use social media to target this untapped young market.
Gym bunnies and keep fit enthusiasts are being specifically wooed to consider the health benefits of watercress when out buying their food.
Tom Amery, managing director The Watercress Company, said: "Older people know how good watercress is, but the young don't buy food for long-term health. They are interested in the more immediate effects of consumption. So we are pushing the performance effect of watercress and how it can help the body recover after intense exercise.
"We think part of the problem is that young people think of watercress as the stuff they grew at school on blotting paper ( that is mustard and cress) or the decorative garnish on a plate. We have to persuade them that it is more than just a bit on the side."
This ancient vegetable( scientific name Nasturtium officinale) was prescribed to patients by Hippocrates and was a staple of Roman soldiers. Originally grown in Britain in spring waters in monasteries it was seen as a poor man's food until it became popular as a cheap green to fend off ailments.
Older people like it because it is high in nutrients and low in calories, just 11 per 100 grams. it has. High levels of vitamin K that is good for blood clotting, vitamin C for iron, calcium to strengthen bones and vital minerals that help lower blood pressure.
Scientists have also found it contains antioxidants that protect DNA damage that is linked to some cancers and it can alleviate stress to the body after energetic work outs.
Nicola Dodd, AHDB marketing manager, said the Instagram campaign had reached 120,000 people in month. "Social media is a great way to reach a young audience. Watercress has not caught up with recent health trends, for example kale and spinach, and is largely overlooked by the young. We want to inspire them to include it in their diet."
Mr Amery added: "We are going to keep up the offensive by giving out free watercress in gyms. We are starting a pilot in Dorset by installing a fridge in gyms to keep watercress fresh before going nationwide. We are also going to target commuters at railway stations with bunches of watercress.
"In the 1920s watercress was sent by rail to cities across the country, sold by hawkers in streets and eaten on the hoof. In winter people were desperate for green veg and watercress was the only one available. Today it's sold in supermarkets and costs from £1 to £1.40 a bag."
Celebrity cook Mary Berry, who grew up on a farm with watercress beds, said recently "My favourite thing was watercress sandwiches with raspberry jam."
A new generation of chefs is also now being enlisted to showcase watercress. Chris Wheeler, head chef at Stoke Park, Buckinghamshire, who has starred on TV's Saturday Kithcn, Sunday Brunch and The Great British Menu, has created a pudding - a watercress, sweet yoghurt and coconut dome with raspberry centre, bitter chocolate shavings and watercress oil.
Watercress is mainly eaten in salads, sandwiches and soups but can be used in stir fries, smoothies, in pesto, chutney, salsa verde and sauces to accompany meat or fish.