If you are a salad lover, as I am, it is more than likely that you are familiar with watercress. Because watercress thrives in clear, slow moving water, many gardeners refrain from planting it. The fact is that the plant is very adaptable and watercress cultivation can be attained in a number of different ways at home. So, how to grow watercress in the home garden? Read on to learn more.
Watercress is a perennial cultivated for its clean, slightly peppery tasting leaves and stems. Seen wild, it grows partially submerged in running water and flooded areas in moderately cool climates. If you have a water feature in your landscape, this is a great place to cultivate watercress, but don’t despair if not.
Watercress can also be grown in consistently wet soil with a soil pH of 6.5-7.5 in full sun, or you can mimic natural conditions by growing watercress plants in a bucket or other container. In the garden proper, you can dig out a 6-inch (15 cm.) furrow, line it with 4-6 mil polyethylene and then fill with 2 inches (5 cm.) of composted soil or peat moss. Of course, if you have a running stream on your property, watercress cultivation is about as simple as it gets.
Watercress can be grown from seed, transplants or cuttings. Watercress varieties abound, but the most common home grown variety is Nasturtium officinale. Prior to planting, choose a sunny location and amend the garden soil with 4-6 inches (10-15 cm.) of composted organic matter down to a depth of 6-8 inches (15-20 cm.).
Seeds are tiny, so they need to be lightly broadcast over the prepared site. Sow three weeks before the frost-free date for your area. This plant germinates best in cool conditions (50-60 degrees F. or 10-15 C.) but not frigid. Keep the planting area moist but not covered with water. Container grown plants can be placed in a saucer filled with water to retain moisture.
Seedlings will appear in about five days. If you are transplanting, space the plants 8 inches (20 cm.) apart once all chance of frost has passed.
Consistent moisture is the number one concern in the care of watercress; after all, water is its milieu. Container grown plants can be placed in a bucket filled with 2-3 inches (5-7.5 cm.) of water so the roots stay submerged.
Although the plant does not have high nutrient requirements, cultivated cress may show signs of potassium, iron or phosphorus deficiencies. A complete soluble fertilizer applied at the recommended rate should mitigate any of these issues.
In the garden, keep the area around the plants free from weeds and mulch to aid in water retention. Snails love watercress and should be removed by hand or trapped. Whiteflies also like the plant and can be controlled with soapy water or insecticidal soap. Spider mites cause leaf discoloration and general deterioration of the plant. Natural predators such as lady beetles, predatory mites or thrips can help control these pests.
The flavor of watercress is best during the cool months of the year. Once the plant blossoms, the flavor is compromised. Watercress harvesting can commence about three weeks after emergence. Cutting or pruning the plants will encourage them to be thicker and lush. Cut the plants to a height of about 4 inches (10 cm.). Wash the cuttings thoroughly and store in a plastic bag in the refrigerator for as long as a week.
Harvesting can continue year-round, adding a boost of vitamins A and C, along with niacin, ascorbic acid, thiamine, riboflavin and iron to your ho-hum salad or an added zing to compound butter or sauces.
Steph is a certified Square Food Gardening Instructor who has been gardening for more than 10 years in Canada where the winters are long and cold, and the summers are unpredictable. She is a volunteer for her community's Incredible Edible project. In the past she created an educational gardening space for seniors and taught classes at a local community center where she created her own curriculum and activities. She participated in several local municipal garden days where she set up a booth to educate citizens about the joy of gardening.
Cress is such an easy green to grow that I’m a bit surprised it’s not more popular. Quite a few people don’t even know what I’m talking about when I mention cress, but I think it’s well worth growing. Let’s start a petition to make cress the next trendy vegetable!
Cress, particularly watercress, is a nutrient powerhouse. The plants contain loads of vitamins and minerals, including vitamins A, C, calcium, and iron. Watercress is also full of antioxidants and is thought to have medicinal properties because it’s high in iodine.
Although watercress (Nasturtium officinale) naturally grows in shallow, running water, it is also easily grown in a planter. As long as the plant’s sun, soil and moisture requirements are met, watercress can even be grown indoors. Gardeners typically grow this edible perennial for its flavorful leaves and shoots, which have a peppery flavor and can be used raw or cooked. Watercress is hardy in U.S. Department of Agriculture plant hardiness zones 6 through 9. Gardeners looking to add a little flavor to their garden can easily grow watercress by simulating the moist conditions of its natural habitat.
Fill a planter with a soilless potting mix that contains vermiculite or perlite and peat. The ideal pH of the potting mix should be between 6.5 and 7.5.
Sow the watercress seeds 1/4-inch deep, allowing 3 to 4 inches between each seed. Cover the planter with plastic and place the container in a tray or a bucket filled with water. The plastic will keep the seeds warm and moist, while the tray or bucket filled with water will keep the potting mix constantly moist.
Change the water every one to three days. Place the container indoors or outside, keeping the temperature between 50 and 60 degrees Fahrenheit. Once the seeds germinate, remove the plastic and begin exposing the seedlings to light.
Transplant when the seedlings develop a second pair of leaves, also known as their "true" leaves. Transplant them to a bigger pot or several smaller pots, spacing them 1 to 2 inches apart.
Set the containers in buckets or trays of water to provide continual moisture to the plants. Change the water once or twice each week to keep it fresh.
Watch for signs of nutrient deficiency. Although watercress is not a heavy feeder, it may develop iron, potassium or phosphorus deficiencies. Symptoms include leaf scorching, yellowing of the leaves or stunted growth. Adding a complete, water-soluble fertilizer to the water, at manufacturer recommended dosages, can solve the problem.
Harvest watercress before the plants begin flowering and before the outdoor temperature rises above 85 degrees Fahrenheit to avoid the flavor becoming too bitter or strong. Harvest it by cutting it back to a height of 4 inches.
Caryn Anderson combines extensive behind-the-scenes writing experience with her passion for all things food, fashion, garden and travel. Bitten by the travel bug at the age of 15 after a trip to Europe, Anderson fostered her love of style and fashion while living in New York City and earning her degree at New York University.
Also called yellowcress, this aquatic or semi-aquatic perennial is native to Europe and Asia where it grows in cold lakes and reservoirs, and along slow-moving streams and rivers. It is a member of the cabbage family, Brassicaceae, that also includes broccoli,mustard, and alyssum, but is not closely related to the annual flower commonly called nasturtium. The plants are fast growing reaching 4-20″ tall and have hollow branched stems that cause the plants to float. The pinnately compound leaves have 3-7 oval to egg-shaped leaflets up to 1/2″long. Terminal elongating racemes of small white flowers 1/4″ across appear from mid to late summer and are attractive to insects, especially hoverflies. Watercress is used in cooking for its peppery taste and is especially valued for salads. Plants can be very invasive. The genus name, Nasturtium, comes from the Latin words nasus meaning nose, and tortus meaning twisted, and refers to the pungent taste. The specific epithet, officinalis, is the Latin word meaning sold in shops and refers the medicinal value of the plant.
Type: Aquatic or semi-aquatic perennial
Bloom: Terminal clusters of small white flowers from mid to late summer
Size: 4-20″ H 39″ W
Light: Full sun to partial shade
Hardiness: Zones 3-11
Care: Remove before becoming invasive
Pests and Diseases: Cercospora leaf spot, Septoria leaf spot. black rot, damping off, crook root, watercress yellows, water snails, slugs, shrimps, springtails, thrips, aphids, caddis-fly larvae, diamond back moth, beetles, stink bugs, cyclamen mite, weevils, flies, wildfowl, deer and muskrat.
Propagation: Seed, division, cuttings
Companion Plants: Not applicable
Keep soil moist – especially with watercress and during the germination stage.
It’s important to keep weeds away from cress plants because they spread the diseases that plague these and most brassicas.
Use mulch to keep the soil moist between waterings.
You don’t need to fertilize cress, but if you decide to, use a liquid fertilizer. Cress isn’t a heavy feeder, though, thanks to its short lifespan, so a little liquid fertilizer goes a long way.
When growing cress hydroponically in a shallow tray of water, remember to fertilize the water with a kelp-based liquid fertilizer. Otherwise, your plants won’t have access to any nutrients.
Because cress grows so quickly and is harvested so young, it’s an ideal candidate for succession sowing. Sow in regular intervals to ensure a steady supply of crispy, succulent greens. Planting every two weeks is a good strategy.
Watercress is listed in some sources as belonging to the genus Rorippa, although molecular evidence shows those aquatic species with hollow stems are more closely related to Cardamine than Rorippa.  Despite the Latin name, watercress is not particularly closely related to the flowers popularly known as nasturtiums (Tropaeolum majus). T. majus belongs to the family Tropaeolaceae, a sister taxon to the Brassicaceae within the order Brassicales. [ citation needed ]
In some regions, watercress is regarded as a weed, in other regions as an aquatic vegetable or herb. Watercress has been grown in many locations around the world. [ citation needed ]
In the United Kingdom, watercress was first commercially cultivated in 1808 by the horticulturist William Bradbery, along the River Ebbsfleet in Kent. Watercress is now grown in a number of counties of the United Kingdom, most notably Hampshire, Dorset, Wiltshire, and Hertfordshire. The town of Alresford, near Winchester, is considered to be the nation's watercress capital.  It holds a Watercress Festival that brings in more than 15,000 visitors every year and a preserved steam railway line has been named after the local crop. In recent years, [ when? ] watercress has become more widely available in the UK, at least in the southeast. Packages of watercress are stocked in some supermarkets and it may be available fresh, by the bunch, at farmers' markets and greengrocers. [ citation needed ]
In the United States in the 1940s, Huntsville, Alabama, was locally known as the "watercress capital of the world". 
Watercress was eaten by early Native Americans. 
The new tips of watercress leaves can be eaten raw or cooked,  although caution should be used when collecting these in the wild because of parasites such as giardia.  Watercress is 95% water and has low contents of carbohydrates, protein, fat, and dietary fiber. A 100-gram serving of raw watercress provides 11 calories, is particularly rich in vitamin K (238% of the Daily Value, DV), and contains significant amounts of vitamin A, vitamin C, riboflavin, vitamin B6, calcium, and manganese (table).
As a cruciferous vegetable, watercress contains isothiocyanates that are partly destroyed by boiling, while the content of carotenoids is slightly increased. Steaming or microwave cooking retains these phytochemicals, however. 
Cultivation of watercress is practical on both a large-scale and a garden-scale. Being semi-aquatic, watercress is well-suited to hydroponic cultivation, thriving best in water that is slightly alkaline. It is frequently produced around the headwaters of chalk streams. In many local markets, the demand for hydroponically grown watercress exceeds supply, partly because cress leaves are unsuitable for distribution in dried form, and can only be stored fresh for a short period. [ citation needed ]
Watercress can be sold in supermarkets in sealed plastic bags, containing a little moisture and lightly pressurised to prevent crushing of contents. This packaging method has allowed national availability with a once-purchased storage life of one to two days in chilled or refrigerated storage. [ citation needed ]
Also sold as sprouts, the edible shoots are harvested days after germination. If unharvested, watercress can grow to a height of 50 to 120 centimetres ( 1 1 ⁄2 –4 ft). Like many plants in this family, the foliage of watercress becomes bitter when the plants begin producing flowers. [ citation needed ]
Watercress crops grown in the presence of manure can be an environment for parasites such as the liver fluke, Fasciola hepatica.  By inhibiting the cytochrome P450 enzyme CYP2E1, compounds in watercress may alter drug metabolism in individuals on certain medications such as chlorzoxazone.