The lush, fiery green you didn’t know you were missing

When you eat a truly fresh leaf of watercress, it activates something called the trigeminal nerve. This is the same nerve, close to the nose, that tingles when you eat a dab of extra-strong horseradish or pungent English mustard. Aptly, the Latin name for the watercress plant is Nasturtium officinale, which translates as “nose twister”.

For centuries, this nose-twisting, vitamin-rich plant was a beloved element of the English diet, whether wild or farmed. But these peppery green bouquets of leaves — known as English bunched watercress — may not be around much longer in their traditional form (though watercress sold in plastic “pillow packs” shows no sign of vanishing).

Hairspring Watercress near Chichester in Sussex is the largest remaining watercress farm in the UK that still hand cuts the cress and sells it in bunches. Edward Scales, who runs the 4.2-acre farm, is the great-great-grandson of George Hair, who started growing watercress there in 1870 using the clear fresh water from its chalk stream. On the Thursday before Easter, Scales and I stood gazing at the soothing sight of watery gravel beds — some of them are the original structures that Hair built — filled with vigorous green leaves, as he explained why he couldn’t see a future in growing watercress this way.

Back in the 1940s, there were more than 1,000 acres of watercress grown in the UK but by the new millennium this had declined to just 150. Most consumers no longer see the value in traditional bunched watercress and even if they did, Scales has found it near impossible to hire new workers to do the labour-intensive work of cutting the cress by hand with a knife, especially since Brexit. “It all ends with me,” he said.

It’s easy to forget just how desirable watercress once was in a Britain that had not yet developed a taste for rocket. In the 1960s, when Scales was born, the demand was so high that his father decided to stop growing wheat to focus exclusively on cress. When Scales joined the family business aged 22, bunched watercress was still a much-loved seasonal food. As Jane Grigson wrote in her Vegetable Book in 1978, the usual way to buy watercress was in bunches tied with elastic bands. Grigson recommended that people who had no fridges should store them like bunches of flowers, in water.

“We sold tonnes of watercress then,” Scales told me, referring to the 1970s and ’80s. “Easter was our busiest time.” Creamy watercress soup made with potatoes and onions was a staple of British cooking and sprigs of watercress were also a ubiquitous garnish with roast and grilled meats, and with cheeses.

The spicy appeal of watercress in England once went far beyond salad. In a sometimes bland cuisine, fresh watercress offered a thrill on the tongue and in the nose akin to wasabi in Japan or chilli in Mexico. In premodern times, wild watercress was said to offer a taste of pepper for those too poor to buy real spice.

Perhaps the greatest forgotten English watercress treat of the 20th century is the watercress sandwich, which for a long time had a far greater popular appeal — as well as a much more interesting flavour — than the stately cucumber sandwich. As Dorothy Hartley wrote in Food in England in 1954, “You get [watercress for tea] in most unexpected places! I have had it in country cottages, in cathedral city tea-rooms and the British Museum.” Hartley’s formula for a good cress sandwich was to butter slices of brown bread and to use sprigs of cress dipped in crunchy salt. “Do not trim off the characteristic little frill of green leaflets that escape beyond the brown edge of the sandwich; their stiff green borders prove the freshness of the sandwich, and add to its enjoyment”. Hartley also suggested a delightful way of serving watercress sandwiches, alternated in squares or triangles with “white bread sandwiches of pink shrimps”, an idea with a feeling of 1950s chic to it.

Hartley’s watercress sandwiches were something to devour with relish but for most of history, watercress was as much a medicine as a food. The plant sprouted up spontaneously in watery spots and, at one time or other, cress was considered a tonic for pretty much anything from baldness to madness. In his poem “Endymion”, Keats writes of “cresses that grow where no man may see them”. Wild watercresses were especially popular in medieval Ireland, where the clear, clean spring waters enabled cress of a wonderful deep-green quality to grow. A 12th-century Irish bard refers to a spring well and its “pure-topped cress”. In the 17th century, the herbalist Culpeper noted that “Water-cress pottage is a good remedy to cleanse the blood in the spring, and help headaches, and consume the gross humours winter has left behind”.

Among its other virtues, Culpeper also claimed that watercress could help “all manner of tumours” (taken as a compress made with butter and vinegar), help with the passing of kidney stones, bring on labour, purge the blood and help with scurvy. The part about scurvy is actually true. Watercress is rich in vitamin C as well as iron and calcium.

It was only in the 19th century that watercress made the leap from herbal cure to food of the masses when it started to be cultivated commercially in England and France, adopting techniques from Germany. It’s unimaginable now, but watercress was once so popular among the British that bunches of it were sold as street food, to be munched out of the hand like an ice cream cone. In Victorian London, the plant was sometimes called “poor man’s bread”, so central was it to working-class diets, at least in the spring and summer. In London Labour and the London Poor (1851), Henry Mayhew gives a heart-rending account of the life of an eight-year-old watercress seller. She heads out to Farringdon market at four in the morning to buy as much watercress as she can carry in her arms and then walks the streets selling bunches of “creases” at four bunches a penny.

Watercress was once so popular that bunches of it were sold as street food, to be munched out of the hand like an ice cream

Watercress became more popular still with the development of the railways. Now, at last, the cress could be brought from the farms in the south of England where it was grown to the markets of London almost as fresh as the moment it was picked. The Mid-Hants Railway, the so-called Watercress Line, opened in 1865, joining the key growing area of Alresford in Hampshire with Alton, where the line connected with London. These were the boom years for watercress. Alresford remains the site of the annual watercress festival, which this year happens on May 15, featuring market stalls and a Watercress Eating Championship. The Watercress Line still runs as a 10-mile heritage steam ride.

The reason that railways were so crucial in the success of watercress is because it is a crop whose glory depends almost entirely on its freshness. This is why Edward Scales stubbornly continues to cut his watercress by hand and sell it in bunches, long after most of his competitors have switched to machine-cutting and plastic bags. Hand-cutting watercress makes no economic sense given that it takes a person four hours to cut by hand what a machine could do in 15 minutes.

Other than Hairspring, one of the very few other watercress farms that still does hand-cut bunched cress is Kingfisher Farm Shop in Surrey. But Scales said he couldn’t bring himself to switch to machine-cutting because the product wasn’t the same. I thought he was exaggerating but when I got home and tried the watercress he had cut for me that afternoon, I realised I had hardly ever tasted watercress this fresh before. It was so mustardy that my eyes watered, and so lush and green that I wondered whether it really could purge me of the “gross humours” of winter, as Culpeper claimed.

The flavour of watercress declines rapidly each day after it has been cut. But most of us are not aware of this decline in taste, so long as the leaves are not actually yellowing. If you do want über-fresh watercress, one way is to try growing it yourself as microgreens on a windowsill or in a garden. The Sarah Raven website sells packets of watercress seeds and notes that you don’t need running water to grow it — “any veg bed will do”, although you do need to keep the soil very moist. Another tip (via horticulturalist Alys Fowler) that I have never tried is to find a stem of watercress in a supermarket bag that has visible roots on it and place it in a glass of water until the roots grow, when you can transfer it to a pot with compost.

By definition, the Spanish watercress that most British supermarkets sell for much of the year is at least five days old by the time it has been harvested, transported, packed and transported again. It’s still much more delicious and interesting than most other commercially grown salad leaves. It just isn’t quite the same as hand-cut cress. Hairspring’s biggest customer is Natoora, which sells the watercress via its app. When Natoora places an order, Scales can cut it and pack it in cardboard to arrive the very next day.

Another advantage of hand-cutting is that the machine-cut stalks get bashed slightly, whereas the hand-cut stalks are handled much less. When I watch Scales cutting cress, he holds each sprig as gently as a hairdresser cutting hair. After a bed of cress is cut, the stubbles are rolled off into the water where they reshoot for another crop. Sometimes a watercress bed will be cut and regrown six or seven times before replanting, making it a very sustainable way to produce salad greenery. Most of the cutting at Hairspring is done by Steve Groom, a smiley white-haired man with a beard whom Scales describes as his “number one employee”. Groom has worked on the farm since he was 17 and is now 64.

Once you have your watercress, what should you do with it? The obvious answer is to eat it fresh and raw, perhaps with a wedge of crumbly cheese. Hartley rightly observed that watercress is better with mild cheeses such as Caerphilly or Wensleydale than with strong ones because it already has enough bite. It also goes without saying that watercress enlivens almost any salad. It pairs especially well with fruit, offering fire to the fruit’s sweetness (watercress and orange with shallot; watercress and peach with Parma ham). The food writer Diana Henry makes a salad from watercress, cherries, almonds and cold poached chicken — pretty much summer on a plate — in which the watercress stops the cherries from being cloying.

Lately, I’ve been cooking with watercress more. Groom told me he liked watercress best cooked with Indian spices as saag paneer. It’s an inspired idea given that in India, saag is usually made from mustard greens rather than spinach as it is in the UK. Even a small handful of watercress added to a spinach saag paneer adds interesting bitterness. I’ve also returned to the purity and comfort of watercress soup. I like Darina Allen’s recipe in Irish Traditional Cooking, which has a very high percentage of green cress to potatoes and onions, and is enriched with a pint of creamy milk. A completely different approach to watercress soup is simply to shred it and add it at the last minute to any clear Chinese broth-based soup with ginger, soy sauce and spring onions.

In French cuisine, watercress was once so beloved that there is a whole category of dishes called à la cressonière. One particularly lovely French way with watercress is eggs baked in a ramekin in the oven on a bed of very smooth mashed potato mixed with puréed wilted watercress. Pour some cream over the yolks before you bake them. This works fine even if your watercress is not the freshest. This is just as well because watercress that is not the freshest is usually the only kind you can get. Then again, it’s a tribute to just how naturally flavoursome these fiery leaves are that they can lose so much of their flavour and yet still taste so exciting.

Bee Wilson is author of “The Way We Eat Now”

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