Finding Watercress in a stream is a good indicator of clean water as it does not tolerate pollution…

A thriving Watercress industry once existed all along the River Wye and Backstream, with many cress beds being worked in Wycombe Marsh as these excerpts from Nineteenth century OS Maps show.

Watercress is a fantastic crop as it contains around 15 essential vitamins and minerals, its health-boosting properties have been known for thousands of years and it has been unaltered by selective breeding - so today’s plants are identical to the plants eaten in, for example, Roman and Saxon times.

Pound for pound, it contains more vitamin C than oranges, is rich in calcium and has more iron than spinach and other leafy greens. Its fiery, peppery heat comes from the plant’s mustard oils and this combination of health and heat is reflected in it’s Latin name - Nasturtium officinale. Officinale denotes use in medicine and herbalism, Nasturtium is ‘nose-twister’.


Watercress has long been a part of the British diet, it grows wild and is easily harvested for free and farmed cress was widely available in many areas. Young cress tastes ok but traditionally it was always thought that it was better when ‘sunburnt’ - slightly older and burnished in colour. It was also never stored in the fridge but kept in a bowl of cold water - the point being it’s best eaten very fresh.

Finding Watercress in a stream is a good indicator of clean water as it does not tolerate pollution. Flowering from May to October it grows best where there is shallow, clear, fast-flowing water. When collecting Watercress from the wild it must be cooked as there is the potential for liver flukes to be present which can cause fascioliasis, a nasty liver disease - cooking kills them.

It is vital never to eat this, or any water or water-edge plant without being certain the water course doesn’t run through agricultural land, or pick it from stagnant water. Always collect from fast-flowing, clean water away from the river bank. Liver flukes comes from sheep and cattle dung, live on wild plants and don’t do you any good once inside you.

It can be mistaken for Fool’s Watercress aka Poor Man’s Cress or Pie Cress, which is found more frequently than Watercress in many places. When crushed, this smells of celery and carrots as opposed to the cressy-cabbagey smell of Watercress, also the sawtooth-edged leaves are in opposite pairs unlike the alternate pairs in Watercress. Watercress flowers have 4 petals and the plant has a solid stem whereas that of Fool’s Watercress is hollow and the flowers usually have 5 petals and form an umbrella shape - it’s an umbellifer.

Fool’s Watercress is perfectly edible, but - and this is important - it is a member of the Apiaceae, or carrot, family (unlike Watercress which is part of the cabbage or Brassicaceae family, hence the smell) which are notoriously difficult to tell apart unless you are experienced. It could be mistaken for Water Parsnip, alleged to be poisonous by some books but commonly eaten, and if your identification goes badly awry you may accidentally pick Hemlock Water Dropwort, readily found along rivers and the most poisonous plant in Britain.

Fool’s Watercress
Hemlock Water Dropwort

Watercress grows well in chalkstreams with their constant temperature of around 11 degrees centigrade and clear, fast-flowing water. The seed is sown direct or seedlings planted at around 2-3,000 stems per square metre. They root quickly in the gravel bed and are fed by nutrients in the water. It can be harvested after as little as 4 weeks - cut by hand with a knife, bunched and crated.

It was, and still is, a popular salad crop, is good with fish and makes a wonderful soup.

Although not directly related to this area I do have a family connection with watercress growing. My great-grandfather was a smallholder and market gardener in Kent and, together with one of his brothers started working on the cress beds in Harrietsham just before the outbreak of WW1. These beds, at Cherry Tree Farm, were owned by my great aunt Lou and great uncle Bill and passed through the family for another couple of generations, but sadly not via my great-grandfather or his brother as they were both killed in the War.

This is a good handed-down recipe for Watercress soup, refreshingly free of modern concerns like exact measurements and timings…

Three big handfuls of cress, a big ‘cut’ of butter, an onion, 3 or 4 medium potatoes, 3 ⅓ - 3 ½ pints of stock, fresh cream, salt and pepper, white cheese. Cook the onions and spuds in the butter, add most of the stock and simmer. Chop and add the cress. When it’s cooked add the remaining stock if it’s too thick. Add some cream and salt and pepper. Grate some cheese over the top.