Sword Fern’s Water Storage Swelling
Nephrolepis cordifolia: Edible Watery Stolons
Edibles are often right under your feet, or my feet as it were.
I had a yard of non-edible ferns. If you like fiddleheads that’s an irritation. That irritation in time lead me to buying a regional fern book to seek out more fiddleheads than I already knew. To make sure I could ID ferns well I started with the ones in my yard, Nephrolepis cordifolia. From the other side of the world they were first found growing in Florida beside a road in Sumter County in 1933. They have since covered much of the state.
Sowrd Ferns From Nepal Found In Florida in 1933
As the N. cordifolia does not produce much of a fiddlehead I ignored it for some eight years as it spread, covering half my property. The identification was rather easy in that of the five Nephrolepis in the state the cordifolia is the only one with marble-size stolons growing off its roots. In fact when I wanted to move ferns to a new spot I often planted the stolons. I thought nothing of them.
My research led me to a scientific paper on the plant from Nepal, Nutrient Analysis of Nephrolepsis, Kathmandu University Journal of Science, Engineering and Technology, Vol 4, No 1 (2008). A team not only tested the Nephrolepis cordifolia for nutritional content but reported children there eat the stolons raw all the time, apparently their favorite wild snack. The team recommended the stolonss be investigated as a potential commercial crop. After rechecking my plants I suddenly realized I had thousands of ferns with edible stolons.
This was a win win in disguise. Florida put the N. cordifolia on the state’s plant pest list, the only fern of about 100 to make it. The state doesn’t like it because the fern is squeezing out the native Nephrolepis exaltata, which is a commercial product. While many ferns species have useable rhizomes only two Nephrolepis have swolen stolons and both are edible, N. cordifolia and N. undulata. What that means is if you have a Nephrolepis and it hasstolons you have an edible. If you don’t live in pan-tropical regions around the world, no problem. There is probably a pot of sword ferns in any number of businesses and lobbies near you. Gently pull the fern root mass out of the pot and look for stolons. If it is a sword fern (Nephrolepis) and it has stolonss, it is edible. Often the N. cordifolia is sold as the N. exaltata because folks don’t know the difference. So you could have fern stolons near you.
Research on the Nephrolepis can be confusing. While online references say there are about 30 species of Nephrolepis in the world a recent study suggests 19 or so, read some consolidation and parsing happened. There still may be some future sorting out in that not all agree there are 19 species. A Florida botanist is quoted on a site as saying there are four species of Nephrolepis with stolons. I contacted him and he flatly denies ever writing or saying any such thing. That is why contacting primary sources is important. The Internet is just a place to start your research. It is not the place to end it.
Nutritionally the stolons of the N. cordifolia are 13.42 percent carbohydrates, 1.34% protein, 1.25 percent starch, 14.88 percent crude fiber, 6.53 ash, 0.75 percent calcium and trace phosphorus. They’re also about 96% water. They can range in color from cream to yellow to dark tan or brown. To me they taste similar Jerusalem Artichokes with the same crunch, a varying amount of astringency, water and potato-like earthy aroma. From the plant’s point of view the tubers are for water storage. The fern is often an epiphyte growing on other plants, most noticeably on palm trees. The stolons can provide water for the dry spells.
Nephrolepis (nef-roh-LEP-iss) is Greek and means kidney shaped scales, referring to the shape of the spoor packets on the back of the fern’s leaf. Cordifolia (kor-di-FOH-lee-uh) means heart-leaf. Where each leaf (pinnule) attaches to the stem (rachis) there is a little protrusion that looks like the bottom of a heart. Identifying ferns is often nearly microscopic in nature. You definitely need a hand lens at least 10x and a lot of patients. The plant is native to Australia and the Himalaya areas. It is found in the Society Islands, New Zealand, Puerto Rico, Hawaii, Florida, Georgia, Alabama, and protected pots elsewhere. If you have a “Boston Fern” in might be the N. cordifolia. Look for the stolons. See my video on said.
Other ferns species with reportedly edible tubers include Angiopteris evecta, Diplazium esculentum, Cyathea medullaris, Pteris esculenta, Gleichenia dichotoma, and Marattia alata. Pteris aquilinum and Aspidium filix tubers have been used to make beer. Tubers are usulally starche and much larger than stolons.
Green Deane’s “Itemized” Plant Profile
IDENTIFICATION: A medium-sized, medium-green, Boston/sword Fern, tapering to both ends, producing below ground scaly round stolons. Leaves pinnate, fertile and sterile fronds similar to three feet long and three inches wide; petioles to eight inches long, Forty to 100 leaflets on each side, oblong-lanceolate with a heart shaped lobe stem end of leaf; leaflet entire to slightly toothed, underside spore packets kidney-shaped
TIME OF YEAR: Tubers are available year round. The plant produces a horizontal root (rhizome.) Off the rhizome are wiry roots, stolons. Growing on the stolons will be the fuzzy hairs. I think calling them “tubers” is not exactly correct, more like water storage units, swolon stolons.
ENVIRONMENT: Shady areas, lawns, waste ground, limestone ledges, wet places, roadsides, in palm trees.
METHOD OF PREPARATION: Eaten raw, out of hand. If you roast large ones in a slow oven the turn into sweet, chewy lumps. Small ones keep their shape but turn to a powder inside that tastes like coffee.
Are there lookalikes that you’re aware of?
If you referring to this particular species, technically no. But ferns can be hard to sort out.
If the small ones taste like coffee, could they be used as coffee grounds maybe? Sounds like an interesting experiment.
Also, are there any poisonous varieties?
How do you plant the tubers? We just dug up a dead fern that did not make it through the winter and found the tubers. I found you as I was trying to identify what in the heck these things were. Do you know of a way to winterized the ferns? Most winters here would enable them to live, but the past 2 winters have just been too harsh. Thank!
I just bury them an inch or so because they are not tubers but swollen stolons, usually near the surface anyway.
I love the article on the Sword Fern with tubers or water pods. I just had to remove quite a few ferns and have lots of the little marbles; was wondering how I tell if I actually have Sword Ferns or are there other ferns with this root tuber that are NOT edible? I am in Bradenton, Florida. Also, do you remove the outer layer before eating and how can I best store them for later eating?
There are five species of sword fern in Florida, but only the one we want puts on these water-swollen stolons. I rub the hairs off but don’t peel them. THere will store a while as is but dehydrating them is the best way.
Hey, if you will dig up and mail me a bunch of fern tubers, I gladly would repay you for costs and efforts.
Please don’t plant these. They’re an invasive species! They need to be eradicated, not propagated. They displace native plant species that native animals depend on. If you have them, by all means dig them up and eat the “tubers”, but don’t let the plants live and multiply!
Are you referring to the tubers on the method of preparation?
Yes I am referring to the tubers. Nothing else is edible.
My child decided to put tuberous sword fern in her mouth. Took a bit of research to figure out that it was the fern, but it fits the description. Tuberous roots, overlapping slighlty toothed leaves, spiney rachis with dark attachment points. She did not swallow, only chewed the leaves. Are the leaves toxic?
That I do not know… I can’t recall any mature ferns leaves being eaten.
What about Nephrolepis Obliterata (Kimberly Queen fern). In seeing a this sword fern in the store I discovered marble sized tubers. Are these edible? Are there any tubers in the Nephrolepis Family that are not edible?
My boy has informed me that he has eaten the little balls on these ferns (which dominate the ground under my oaks) and his verdict agrees with yours. None of the humans at my house have eaten the leaves, but my chickens *love* them. Of course, the chickens love to eat roaches too…
I am from Nepal. I have eaten those tubers which we call it as PAANI AMALA.
But I am curious to know if there are any species/virieties of those tubers found in New Zealand are still edible?
In Nepal it is reported that it is consumed by the Diabetic and Jaundice patient to cure
Yeah but they are crazy invasive! So I suppose you can dig them up and eat them, but please please don’t encourage folks to PLANT them. Destroy them ! Plant native ferns.
Did the entire “Alone” cast of experienced hunter-gatherers twice, when filming themselves living alone on Vancouver Island, overlook these common edible fern roots, the “swollen stolons” of the ubiquitous Sword Ferns?
Surely some of these smart people did their homework on the local edible plants before leaving to survive there alone.. with no reliable source of above ground carbohydrates…
The contestants never said that when the large marble-sized ones were roasted they turn sweet & chewy. That they boil like potatoes.
And that no size is too small..roasted tiny ones crush into powder with your fingers and Make a good hot drink with 13.4% carbs & fiber.
“Alone” people starved on beds of fern fronds.
Never once did a fish soup, or greens or a mushroom dish or a salad include the invasive Sword Fern overtaking the Island.
A $500,000 mistake.. with all the countless tons of hairy tasty carb-marbles growing inches below their feet.. I watched it & rewatched it not happen.
The amazing Alan Kay-the “last person standing” on episode #1- said he didn’t “know anything yet about the edible plants” there. Why not?
Before Alan Kay won the contest (“So soon?”) he told us what it’s like: “I feel like I’m starving.”
Why?
Ignorance & fear of the unknown?
I would say the simple answer is that in today’s YouTube driven survivalist/ woodsman/bushcraft world, foraging is not at the forefront of woodland food gathering techniques. Sure, these guys dabble and know some stuff, but not extensive. It’s mixing of two world’s. I don’t mean to sound degrading by this next comment but bushcraft guys are more about shelter, hunting,fishing, firecraft ect. Where foragers are more on a naturalist, environmentalist types. Bushcraft is more limberjack types and foraging is more hippy types if you will. I feel confident in that statement as I move in both circles and honesty see it as a rarity they cross to deeply.
I was just watching Alone and I to wondered why they were not eating fern tubers and purging their shellfish before cooking them
My research on N cordifolia ( Nutritional composition) is comparable.
N undulata also contained similar nutrient as well.
SO BITTER, tasting the raw tubers in early sept. Eating the not so dark medium sized thinking those are the most edible, but UGH, they don’t taste good. Any recommendations for fermenting them? I’ve got 2 large mason jars full from a weed-through/hardvest I did.
What a sweet and exciting find!
Thank you for providing the safety, nutritional, and prep I structure to validate this (invasive) but pearl- like treasure
Are the nephrolepis cordifolia leaves eaten as vegetables ?
No. I would have said so if they were.
Hey. I went a read through every comment. No, I didn’t watch some person starve to death filming some real life hunger game to point out that sometimes it is right under your nose because there are nursery rhymes that deliver it better and I didn’t have to watch a helpless person starve and comment on some internet thread like “hey, I film TV, im that guy, so ya know, these ferns, all this great research and all, useless, because people think about how 500,000 could literally save everyone they’ve ever loved so why not if all we are is a Darwin Theory gimmick to the nitwit that can’t see it only goes so many ways from here and from what that guy said about hearing someone starve for the once in a lifetime jackpot, as someone who is human and has played a slot machine, I’m game, wish you were, too. Also, quit asking this guy the same questions. His article and responses in the first like 3 comments already have answered everything but you all are apparently too dumb to do research. You just talk about what you found without any care or research to know about it for yourself. props dood.
I was just watching Alone and I to wondered why they were not eating fern tubers and purging their shellfish before cooking them.