Growing Watercress

By Penny Ossowski

 

Watercresses (Nasturtium officinale, N. microphyllum), aka Scurvy Grass, is a member of the Brassicaceae family, closely related to broccoli, brussels sprouts, cabbage, turnip, mustard, horseradish, garden cress, kohl rabi, kale, and radish but not closely related to the ‘nasturtiums’. Watercress is used largely as a vegetable but is even more important as a herb, the term ‘officinale’ as part of its name refers to it being noted in the ‘official list’ of the most important medicinal herbs. There are few herbs that are richer in the large array of vitamins and minerals, which are essential to the human body. Watercress is native to the Mediterranean, Europe and Central Asia where it originally grew as an aquatic or semi-aquatic, perennial plant. It is one of the oldest recorded leaf vegetables consumed by humans and can be traced back to the early Persians, Greeks and Romans as part of the diet for making their soldiers healthier and improving the bodily growth of their children. Records report its cultivation in Germany in the 16th century and Britain in the early 1800’s. Watercress has been naturalised in many countries throughout the world.

 

As I liked to use watercress in my meals I first tried growing it several years ago. First, after research, I tried growing it in water (this is the best way to get it started) but it seemed to lack nutrients, encouraged mosquito larvae and my cat loved to drink the water from its container. So I then planted it into the garden bed, after a few moves I found a suitable bed for it, except in the middle of summer. I grow it in a relocatable polystyrene container. In its natural environment watercress grows in streams of fresh flowing water, whose origins are in chalky or limestone soils but for many home growers this is not an option. If growing in a pond or water container, water should be changed frequently, not allowing slime/algae to grow. It should not be grown in water near animal waste as this can be a haven for parasites such as the liver fluke. Ideally it is suited to growing hydroponically and can also be grown in a mix of perlite, vermiculite, coco peat or soilless potting mix. If growing in garden soil select a damp position prepared with lots of compost. Watercress prefers a location with a pH between 6.5 and 7.5 and in full sun but in our hot summer it will do better in partial shade. It makes an ideal container plant where soil can be prepared and kept to the optimum requirements. Watercress can be grown from seeds or cuttings. Seeds should be sown into containers/seed trays filled with a mix of garden soil and/or compost with some added garden lime, kept moist at all times in a partially shaded area. Seedlings can be transplanted when they have about 6 leaves.

 

The easiest way to grow watercress is by cuttings from an established plant or from a bunch of watercress purchased from the green grocer. Watercress will produce roots from each leaf node and this can be encouraged by pegging leaf nodes to the ground or placing into a glass of water until roots are formed then plant out to your preferred location. If your watercress gets too lanky cut it back to a couple of leaf nodes from the base and it will shoot again. Regular harvesting of the tips will encourage your plant to grow bushier with more shoots for the next harvest. Watercress has few pest and disease problems. Caterpillars like their tender leaves, occasionally aphids, whitefly and spider mites may take up residence but most of these can be easily dealt with by regular inspection, hand removal and an adequate water supply.

 

You can buy Watercress seeds online from Eden Seeds.

 

As watercress does not store well it needs to be harvested regularly. In my garden the best flavoured leaves are produced from Autumn through to Spring, once they start producing clusters of white and green flowers the leaves become bitter. The best way to store it is frozen for use in cooking or cooked and pureed for using in soups and stews.

 

Pick a sprig of watercress to eat when you’re out in the garden to freshen your breath and tastebuds. Some of the traditional ways to use watercress is on sandwiches, in salads and soups, but it also goes well as pesto, in stir fries, stews, dips, entrees, omelettes, pies, quiche, casseroles and in rice dishes use it anywhere green leafy vegies are called for. Watercress makes an edible and attractive garnish on platters of vegetables and/or meat and goes surprisingly well with pawpaw and pineapple. In England, watercress used to be a staple part of the working class diet, usually eaten for breakfast in a sandwich but if the family was too poor to buy bread they ate it by itself and it became known as ‘poor man's bread’. Watercress is best eaten fresh so pick it as you need it.

 

Nutritionally watercress has more iron than spinach, more calcium than milk and three times as much Vitamin E as lettuce as well as being packed with vitamins A and C, having significant amounts of iron, calcium and folic acid, and is also low in calories.

 

On the Island of Kos around 400BC Hippocrates, the Father of modern medicine, is said to have deliberately located his first hospital beside a stream so that he could grow a plentiful and convenient supply of watercress with which to help treat his patients. Herbalist John Gerard extolled watercress as a remedy for scurvy as early as 1636. As a herb it is said to be helpful for eliminating toxins from the body, as a diuretic, expectorant, laxative, stimulant, antacid, antioxidant, antibiotic, antiseptic, antibacterial, hair tonic, aphrodisiac, digestive, for toothaches, diabetes, tuberculosis, cancer, emphysema, migraine headaches, anemia, eczema, kidney and liver disorders, boils, warts, hiccups and even freckles. Other than kelp, watercress is the best source of iodine which is helpful for strengthening the thyroid gland. Eating a bag of watercress is said to be a good cure for a hang-over. To ease aches and pains make a tea with 1 cup of hot water, 1tbsp chopped fresh watercress leaves, a squeeze of lemon and sugar to taste.

This plant is well worth a place in your garden or courtyard or balcony.

 

Be aware that quantities of watercress can interfere with some medications, (Acetaminophen, Chlorzoxazone, Warfarin) please discuss this with your medical practitioner.

 

Some interesting Watercress facts

·      The early Romans prepared water cress with oil and vinegar and served it with pepper, cumin seed and lentiscus (leaves of the mastic tree).

·      Captain James Cook was able to circumnavigate the globe three times, due in part, to his use of watercress in his sailors diets to prevent scurvy.

·      Watercress is recorded as being on the menu for the very first Thanksgiving with the Pilgrims and the American Indians.

·      "The American Indian used watercress for liver and kidney trouble and to dissolve kidney stones. It is rich in iron and other valuable mineral elements and its blood purifying and system cleansing     properties cause it to be used extensively as a blood purifier

 

Nutritional Information

Serving Size: (100 grams raw)

Calories: 11                               Kilojoules: 46.2

Total Fat: 0g                             Cholesterol: 0mg

Total Carbohydrates 1g             Dietary Fibre 1g

Sugars 0g                                 Sodium 41mg

Protein 2g                                 Vitamin A 4700IU

Folate 9 mcg                             Vitamin B6 0.129 mg

Manganese .244mg                   Vitamin C 43 mg

Thiamin .09 mg                          Vitamin E 1mg

Vitamin B6 .129mg                    Vitamin K 250 mcg

Calcium 120mg                         Magnesium 21mg

Phosphorous 60mg                   Potassium 330mg

Niacin .2mg                               Riboflavin .12mg

Iron .2mg                                  Zinc .11mg

 

 

Potage Cressonniere (Watercress Soup)

¼ cup butter                                         1 clove garlic, minced                            2 cups chopped onions

300g thinly sliced raw potatoes              1 tbsp salt                                            ¾ cup water

¼ teas ground black pepper                  150g watercress                                    1½ cups milk

1½ cups water                                       2 egg yolks                                           ½ cup cream

 

Directions

1.   Heat the butter in a large saucepan. Add the garlic and onions and saute until tender, about five minutes.

2.   Add the potatoes, seasonings and three-quarters cup water. Cover and bring to a boil. Reduce the heat and simmer fifteen minutes or until the potatoes are almost tender.

3.   Cut the watercress stems into one-eighth-inch lengths. Coarsely chop the leaves.

4.   To the potato mixture add all the watercress stems, half the leaves, the milk and water. Cook fifteen minutes. Puree in blender or put the mixture through a food mill. Return to the saucepan and reheat.

5.   Blend together the egg yolks and cream. Gradually stir into the soup and cook, stirring constantly, until slightly thickened. Garnish with the remaining watercress leaves

 

 

Watercress Pesto

100g watercress                                    2 tbsp pine nuts                                    grated pecorino

sea salt                                                 ground white pepper                  your favourite neutral flavoured oil

 

Directions

Rinse the picked watercress and dry then place the watercress into a processor with a drizzle of oil and pulse until roughly chopped.

Add in the pine nuts and pulse again until they are roughly chopped.

Add a heaped tablespoon of grated pecorino and another good drizzle of oil and pulse again until a paste forms (leave mixture a bit coarse)

Spoon the pesto into a bowl and taste, adjust with salt and pepper and add more grated pecorino and olive oil to form a thick slurry.

Store in the fridge in a sealed container - make sure you store it under a layer of oil to stop it from discolouring