Nasturtium officinale (Watercress)
|Also known as:||Small-leaved Water-cress|
|Habitat:||part shade, sun; cool, shallow water, muddy banks, streams, springs, seeps, wet ditches, ponds|
|Bloom season:||April - July|
|Plant height:||4 to 15 inches|
|Wetland Indicator Status:||GP: OBL MW: OBL NCNE: OBL|
|MN county distribution (click map to enlarge):|
|National distribution (click map to enlarge):|
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Elongating racemes at the ends of many branching stems, with blooming flowers clustered at the tip. Flowers are about ¼ inch (to 6 mm) across with 4 rounded white petals, 6 yellowish stamens, a short central style, and a purplish green ovary.
Leaves and stems:
Leaves are 1 to 6+ inches (to 15+ cm) long, ¾ to 1½ inches wide, compound with 3 to 9 leaflets, occasionally more. Leaflets are lance-elliptic to narrowly egg-shaped with somewhat irregular edging, typically rounded at both ends, the terminal leaflet rather larger than the rest and may be nearly round in shape, though leaflets can elongate, becoming more narrowly lance-oblong. Stems and leaves are hairless. Stems may be erect, reaching a height of 3 feet or more, but more typically float on the surface of the water or sprawl across mud, rooting freely at the nodes and forming dense mats.
Fruit is a slender pod, 3/8 to 1 inch (1 to 2.5 cm) long, slightly curved, spreading to somewhat ascending, and have a short, abrupt beak at the tip. Seeds are oval, reddish brown when mature, and arranged in 2 rows.
Formerly known as Rorippa nasturtium-aquaticum, this is the same Watercress found in your local grocer's produce department. A widespread and problematic invasive of clear streams, springs and brooks, it can rapidly spread out on the surface of the water, choking out natives. The stems and leaves are crisp and can be used as a salad with a pungent radish flavor. I do like harvesting it wild, but cleaning off aquatic insects and spiders is a chore as well as running the risk of beaver-fever (girhardia), or ingesting the toxins in our polluted waters. When not fruiting it is virtually indistinguishable from Nasturtium microphyllum (Rorippa microphylla), also found in Minnesota. N. microphyllum has pods that are generally longer and more slender, containing seeds in 1 row, and is aptly commonly called One-row Watercress.
Like many weeds, Watercress is much more widespread in Minnesota than herbarium records indicate; there are currently over 130 reports in MN on the national weed tracking system EDDMapS.
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- Watercress plant
- erect Watercress plant with elongated leaflets
- a colony of Watercress
- Watercress in a floodplain
- Watercress in a flowing stream
- a dense infestation of Watercress and Forget-me-not, along the Mississippi River
- leaves in early spring
Photos by K. Chayka taken at Pine Bend SNA and Whitewater Wildlife Management Area. Photos by Peter M. Dziuk taken in Dakota, Winona and Washington counties.
Have you seen this plant in Minnesota, or have any other comments about it?
on: 2012-01-26 13:37:22
do you or do you know where i could get a list of local gardens or gardeners where i could go to pick my own water cress? when i was young my grandparents had a cabin on the mississippi where the property had 3 fresh water springs and the water cress was abundant and available year round. i really miss being able to use it in recipies. any help would be much appreciated thank you
on: 2012-01-26 17:10:49
Watercress, an invasive species, is choking streams in the Whitewater area of Winona county. Feel free to go down there and harvest all you want. ;)
If any gardens or garden clubs are promoting this weed, it would be better to educate them as to the invasive nature of this pest, and stop its spread before it does more damage to local ecosystems.
on: 2017-05-11 12:48:23
Is it legal to pick up watercress in MN? Does one have to buy a license to pick it?
on: 2017-05-11 17:59:29
Tom, if I had my way I'd let you take all of it, everywhere in the state, free of charge. But it's not my call. You need the landowner's permission to collect anything on their property, weed or not, and be that a private landowner or some city, county or state agency. So find out who owns the land and ask for permission to harvest it.
on: 2017-12-14 16:04:45
Hello, We love to harvest some organic watercress this spring and fall. If you know the exact location of where in the twin cities areas that have these, we would love to come and harvest some. I heard watercress loves to grow in creeks and streams. Also, is it legal to pick them from the creek or stream with public access? Thank you, Tony
on: 2017-12-14 16:22:29
Tony, please see the above comments regarding harvesting watercress from the wild. Bottom line: get the landowner's permission. But know that nearly all the waters in the metro area as well as SE MN where this is prevalent are polluted with atrazine and other toxins. It may not be safe to eat.
on: 2018-05-10 17:22:38
We went to check on the morels in Whitewater State Park and saw wild leeks. We stopped to dig some leeks and the park ranger told us we can't harvest anything from the park other than morel mushrooms and berries. She gave us a brochure which states we can't harvest watercress. Bummer - because last year we harvested some after checking with the park office.
on: 2020-01-05 11:54:23
Sad to have found it, it was abundant in a feeder stream going into Lawrence Creek. Located it 1/4/20.
on: 2020-05-23 22:50:28
There are TONS in the springs that flow into 9 mile creek in Bloomington
on: 2021-08-08 01:18:49
The MN DNR has resources available online to find spring-fed streams - where watercress grows. They really make it easy. A good rule of thumb is to only harvest in wild or native trout streams. WI has a scale classification for trout streams. Class 1 WI streams are where I would only harvest from as they offer the best water quality and thus the most abundant wild and native trout reproduction. MN doesn't have such a scale unfortunately which means you'll need to do your own research. Google the MN DNR spring inventory map and cross reference with the MN DNR streamfinder map and stream profile page. It's a very incomplete resource, but it offers some info at least. I personally wouldn't consume anything south of the 218 area code until you reached the Driftless region and go far from the cities and farms.