Watercress

~ Watercress ~ (Nasturtium officinale)

Being spring, I’m currently planting Watercress seeds in my garden, where I’ve found it grows well in a damp, shady part of the garden. Once established, it’s such a generous plant, providing handfuls of fresh, peppery greens to add to salads, sandwiches, soups or rustic meals.

Watercress is a wild perennial member of the Brassicaceae family, growing naturally in running water, streams, springs and other wet places. Originally from Europe and Asia, it has  now naturalised in many parts of the world.

Watercress is considered one of the oldest known leafy vegetables eaten by humans, with a history stretching back thousands of years. The ancient Persians, Greeks and Romans all valued it, not simply as food but as a medicinal plant.

Hippocrates, often called the father of medicine, is said to have grown Watercress beside the first hospital he established on the island of Kos around 400 BC. It was traditionally used for a wide range of ailments, from respiratory complaints and digestive troubles to skin problems and what was historically described as ‘blood purification’.

The Persians apparently noticed that their soldiers seemed healthier when Watercress was included in their diet, while Roman traditions associated it with courage and bold decision-making. It was also regarded in various traditions as an aphrodisiac and there are even old accounts of Watercress being used as a hangover remedy!

Some of these traditional claims are more ‘interesting’ than scientifically proven, but modern research has given us some fascinating reasons to pay attention to this little green plant.

Watercress is incredibly nutrient dense. It contains vitamin C, vitamin K, carotenoids including beta-carotene and lutein, along with minerals such as calcium, iron, magnesium and manganese. It is also rich in plant compounds called glucosinolates.

These glucosinolates are the same family of compounds that give many Brassica plants their distinctive pungency. When the plant tissue is chopped or chewed, they can be converted into compounds called isothiocyanates, including phenethyl isothiocyanate (PEITC). These fascinating compounds are being studied for antioxidant, anti-inflammatory and potentially protective effects in the body.

In other words, that fierce peppery flavor isn’t just there to wake up your taste buds. It is part of the plant’s chemistry.

Watercress was also traditionally valued as a source of vitamin C. Herbalists used it for scurvy, and it was included in historical accounts of sailors’ diets, including those of Captain James Cook.

In Britain, commercial cultivation took off in the 19th century because Watercress is extraordinarily perishable. The arrival of the railway allowed freshly harvested cress to be picked in the afternoon, transported to the station and arrive in London markets the following morning.

The Hampshire town of Alresford became so closely associated with the crop that it is now known as the home of British Watercress. It even has an annual Watercress Festival, complete with food stalls, demonstrations and a Watercress Eating Championship.

Watercress is delicious eaten raw when young and tender, particularly before flowering. I love it scattered through salads, tucked into sandwiches, stirred through potatoes or simply piled onto a meal. Its flavor is somewhere between mustard, horseradish and wasabi.

It can also be cooked into soups and sauces. Historically, Watercress soup was particularly popular in Britain and was once believed to ‘cleanse the blood’.

But there is one VERY important thing to remember when foraging Watercress.

Watercress should never be treated as automatically safe simply because the water looks clean.

Because it grows directly in water, it can accumulate contaminants from its environment. Waterways receiving livestock or manure runoff can present a risk of bacterial contamination and parasites, including liver fluke. Contaminated surface water can also carry organisms responsible for gastrointestinal illness.

So when gathering Watercress, know your water source. Avoid waterways downstream from farms, sewage, urban runoff, industrial activity or other possible contamination. And if you don’t know the history or quality of the water, don’t eat the cress raw.

One final botanical curiosity...

Despite its Latin name, Nasturtium officinale is not the colorful garden Nasturtium that many of us grow and eat. Garden Nasturtium (with the Orange trumpet shaped flowers and round leaves) is Tropaeolum majus, a completely different plant family.

If you’d like to learn more about identifying and safely gathering the wild plants growing around you, have a look at my Foraging Guides. I’ve created guides for different seasons and habitats to help you confidently identify, forage and use the abundance of edible plants all around us.