Watercress (scientific name: Nasturtium officinale) is a semi aquatic plant. It’s a productive plant, well adapted to aquaponics.
The watercress roots system is well developped on the media surface. In fact, roots devellop on the whole stemp as long as it’s in contact with nutrients. This specificity allows 2 things:
Since the roots can develop on the whole stamp, cuttings are extremely easy. The plant will actually propagate itself and colonize the whole growbed.
Watergress can grow on anaerobic soils!
Growbeds are sometimes clogged and most plants can’t handle anaerobic roots stress. But watercress is one of those rare plants which can handle such conditions. The shallow roots are still able to breath and keep the plant in healthy conditions. Hence, it’s a very good plant for beginners.
Hence, I choose to colonize the edge of my holistic aquaponics fish tank with watercress. The fast growth of this plant will absorb a nice quantity of nitrate. It will also produce an a quantity of very precious crop…
A qualitative plant
Watercress is not only easy to grow, it is also a very good plant to consume. It has a nice peppery taste and a crunchy texture. You can consume it in salads or in other meals. Watercress presents many nutritional benefits. Rich in Vitamin K and Vitamin C, it also decrease blood pressure.
Watercress price is variable but goes from $10 to $20 per kg depending on the countries. A nice crop to feed your family and neighborhood community with!
Not the classic gardener’s plant
Watercress is one of the easiest plants to grow in aquaponics. But not in a classic garden! Being a semi aquatic plant makes it difficult to cultivate for the classic gardeners. Hence it’s a very nice crop to grow and share with others.
Watercress culture in aquaponics
Watercress grows well from spring to end of autumn. you can sow the seeds as soon as the temperature exceeds 8C. Another option is to get cuttings from a friend or buy some from the shop.
Watercress isn’t specially attracting insects. However, you will occasionally find slugs, aphids and caterpillars. See our the pest control guide to manage your insect population.
You can harvest your watercress as soon as it reaches 12cm height. Make sure to not pull the roots, simply harvest the shoots. Doing so you will be able to harvest the same plant every 2 weeks.
A beautiful plant
Watercress is a luxurious plant with a generous green. As it grows naturally near streams and river hedges, I think it’s a nice one to have around an ornamental pond. It can only enhance the natural aspect of the ecosystem.