Seed Count: Approx. 100 seeds
Days to Maturity: 20-60 days
Description: True Watercress is one of my absolute favorite greens to eat. It is a highly nutritious semi-aquatic herb, with small dark green leaves, a crisp texture, and a fresh peppery taste. They are a great addition to salads and sandwiches, but my favorite way to eat them is sauteed in a little butter with garlic and onions for breakfast. This cress is a creeping perennial (zones 6-9) that naturally grows wild and hardy along running streams. It grows very rapidly, and requires a bit more attention than other cress varieties, due to its need for frequent watering. However, this is an easy fix if grown in pots of soil that are placed in a tub of water and changed weekly. It does not do well in too much heat, so I prefer to grow mine indoors.
How To Grow
Sowing: Watercress can grow nearly anywhere, as long it gets adequate water. It prefers rich, moist, non-acidic soil (PH around 7.0), and full sun. If you live in a hot area, try growing it in a slightly shaded part of your garden, or indoors, which is my preference. Watercress is a cool weather plant, since excess heat tends to give the leaves a bitter taste. It can be sown in the spring and in the fall in most areas. After the last spring frost or late in the summer, direct sow your seeds by barely covering the seeds with soil, ideally in full sun, near running water. However, you can grow them outside or indoors in pots of soil, placed in a containers of water, just make sure to switch out the water every week. You can also grow them regularly, in dirt, as long as you make sure to water your plants frequently and to keep the soil wet. I prefer to grow mine indoors, aeroponically, in my tower garden. Thin plants 3-6" apart when the seedlings appear. If you are planning to harvest your watercress at a small size, the plants can be spaced 2-3" apart. Keep the soil moist for rapid growth. For a continuous harvest, sow a new crop every 10 days.
Growing: Weed control and sufficient moisture are crucial to the healthy growth of watercress. Since it has shallow roots, take care not to disturb them when removing weeds. A layer of mulch, if planting outdoors, often helps conserve moisture and control weeds. Companion plant cress with bunching onions, chives, peppermint, spearmint, and wintergreens. Watercress can also be inter-planted with other small crops. Slugs can be an annoying pest, while you grow this green, but growing it in containers and keeping it off the ground will stop this problem.
Harvesting: Cress can be harvested at any size, from micro-greens up to a height of 6". However, watercress is best harvest young, since its stems can get tough and bitter the older it gets. If part of the stem is left above ground level, new leaves will continue to grow, at least once. The leaves should be used fresh, since they do not store well, but can be kept in the refrigerator for up to 2 days. Watercress reseeds itself readily, if left alone after flowering, but the seeds can easily be gathered. Soon after blooming, the flowers will begin to fade and the seed pods will develop. Wait until most of the pods ripen to a light brown before picking the whole cluster of pods. Since the pods will split open and drop their seeds when fully ripe, watch them carefully. You can also place a mesh jewelry bag over the seed heads to catch them, just in case. Spread the heads out in a protected location away from direct sunlight to dry fully, then thresh out the seeds and store.