Happiness is a root called Hopniss

What's long and pink and gets stuck in tarts? Rhubarb, of course. Who says old jokes are the best? Let's move on - sharpish. So, what root crop is long and thin with bulges like a pet-swallowing python and tastes really good? That's a bit more difficult for the uninitiated. The answer, as zealous enthusiasts of future foods may have already guessed, is groundnut (Apios americana).

This twining legume with tasty tubers was a mainstay of the Pilgrim Fathers as they struggled to survive their first few years in North America. It was a staple of the native peoples for centuries before this. It may even be the "potato" that was supposedly introduced to Britain by Sir Walter Raleigh from the Virginia colony in the 1590s.

Once seen, the swollen lumps scattered on the sinuous rhizomes make for easy

identification. Not only does it taste nice, it will survive our winters (and summers) and is nitrogen fixing. This must surely be the most uneglected of the shamefully neglected potential new root crops. I mean to say, down in Deputy Dawg Country, or a little over the border in Louisiana, they had a university department actually trying to domesticate this species. Just as they was making some progress, the darn funding got pulled from under 'em and they was left high and dry, doggone it.

I've done a bit of research into alternative names for groundnut - Apios - blame it on long winter nights and few friends. Some of the most colourful lurk in a yellowing copy of the Apios Tribune from back in the days when the plant's future as a new crop was assured - supposedly. Yes, Apios had its own enthusiasts' newsletter, produced under the aegis of the Louisiana State University team at Baton Rouge.

Check these out: nu-nu, chicamins, maskoseet, chiquebi. These are all derived from native languages, although the article doesn't specify which ones. To us Brits, "groundnut" means peanut, Arachis hypogaea. If we're serious about promoting this plant, then we don't want to confuse Arachis with Apios. Sweet potato and potato are bad enough, especially seeing as "potato" is a linguistic flea that jumped from its original host Ipomoea batatas (sweet potato) and latched onto Solanum tuberosum. To avoid confusion, Americans sometimes call Ipomoea batatas "yam"; what they call yams (Dioscorea), I'm not sure. Just when the waters are getting a little turbid in Lake Etymology, up steps plucky New Zealand with the idiomatic use of "yam" for oca (Oxalis tuberosa). The moral of this diverting digression? Learn scientific names and use them. It’s not that painful and can be an effective chat-up line.

There's another reason. To us Brits, groundnut is also a name that reeks of incompetence, obstinacy and downright stupidity, from the dying days of the "empire on which the sun never sets" (huh). I'm referring of course, to the infamous "Groundnut Scheme", or should I say debacle, of the late 1940s, in which vast areas of Tanzania were ruined by the inappropriate cultivation of peanuts at the behest of the British government and all funded courtesy of war-weary tax payers. So, rather than finding Apios guilty by association with that name, I propose that we find an alternative moniker. Apios, by the way, is derived from apion, Greek for pear, a reference to the ovoid shape of the tubers - information all aspiring slumdog millionaires should stash for future reference.

It seems that the root word for Apios americana in the Algonquin languages of the eastern USA is "pen". This occurs in various forms such as openauk, penak, etc. "Hopniss", as in this post's title, is derived from the same root word too: o-pen-iss. For some reason "hopniss" seems to have broken out of its original Delaware boundaries and expanded its range above and beyond nu-nu and all the others. It's not such a bad name, having currency among wild food enthusiasts such as Sam Thayer, whose article on Apios americana is here. He provides plenty of interesting information, as well as some recipe suggestions. The climbing, winding stems also have a passing similarity to hops, so perhaps the name is reinforced by this happy, I mean hoppy, coincidence.

Anyway, I mentioned the work of the Louisiana team from Baton Rouge, who seem to have had some success in breeding improved Apios varieties - son of a gun they found big ones on the bayou, or at least they bred them. That’s as maybe, but they won't be the best for growing up here. The climate's just too different - like it's a lot cooler, a lot less sunny: our summer = Louisiana winter. Perhaps I jest, a little, but only a little. I was sent some seeds from the Louisiana project, but not a single seedling showed any promise in our climate. None of the Louisiana selections ever flowered, nor did they produce worthwhile tubers. It seems that this is no mere coincidence. Further trawling led me to a paper by some Japanese researchers. According to the authors, Apios starts producing the long rhizomes early in the growing season, but they don't swell much until after the plant has flowered.

Luckily for us, hopniss has a massive range, from the Gulf Coast right up into Canada. The future's bright, the future's brown.

Less fortunate is the fact that these northern adapted plants are almost always sterile triploids and thus difficult to use in any breeding programme I'm likely to be able to undertake. The northern-adapted triploid varieties, which flower every year, seem to do much better here in terms of yield, which is after all, what we’re all interested in, or at least I am. Ironically, the fact that they are sterile probably helps, as the plant doesn't waste time producing those resource hungry seeds. That still leaves me up a bit of breeding blind alley with defective sat nav if the destination is a new crop for cool temperate regions. There are, however, some fairly northerly locations in the USA where diploid plants can be found; if anyone knows anyone living in these areas who might be able to go out and collect seeds from these on-the-edge diploids, I'd be very grateful. Calling the citizens of the following locations: Oneco CT, East Otis, MA, Erving MA and anywhere else in New England where the distinctive big pods follow the attractive pink or burgundy flower clusters.

I've also discovered a Dutch seedsman by the name of Geralt Joren who runs Allseeds and has been breeding Apios, sorry, hopniss, for a few years. I'm very keen to try out his seedling selections in the future. He’s got some other interesting stuff too.

Excuse me while I get all misty-eyed for a moment. My first hopniss plant came from Ken Fern of Plants for a Future back in the days when I was young and rhizophilia was at its most intense. Happy days and great expectations.......

I've mellowed a bit since then, but I've also gained a few more accessions, purchased from various nurseries in the UK , or gifted by other enthusiasts. They vary in the colour of their flowers and the degree of hairiness shown by the leaves and stems. The tubers seem to vary in shape as well. Ken’s is still one of the best. One day, when a mysterious benefactor secretly deposits some serious wonga in my coffers, I'll get round to doing proper characterisation of them all, measuring emergence date, vigour, yield and taste of this eminently edible, high protein, nitrogen fixing root crop. Then comes the breeding work – I can’t wait. Details of my Pay Pal account are available on request, Mr Magwitch.


Axel said…
Nice blog and nice to read about hopniss or potatisböna (potatobean) as we call it sweden!
It's really interesting that they undertook it to make hopniss-varieties for commercial growers. It's sad they were unable to continue.

I found something interesting about hopniss while searching the internet. Maybe Japan has some nice cultivars of it!? They call it hodoimo, i'm not sure if its Apios americana, A. priceana or A. fortunei that they are growing though. But they seem rather serious about, making chips (crisps) some kind of drink and some kind of candy. I even saw a picture of some tubers on a stick on a barbeque!
Look at this: http://hodoimo.naganoblog.jp/

I hope you have a nice harvest later on!
Rhizowen said…
Hello Axel

Nice to hear from you. I know that Apios americana has been introduced to and is cultivated in Japan on a small scale. The URL you give shows some intriguing possibilities, both in terms of cultivation and preparation for use in soup. Another name, apparently, is "apiosu", which kind of figures. I'm guessing this is Apios americana, but I'm not certain. I read a paper about the introduction of hopniss to Japan, but can't seem to lay my hands on it at present. I think the work was carried out at Tohoku University by someone called Hoshikawa. It's quite possible that Japan would be a good source for improved cultivars and cultivation techniques.

Does hopniss grow well in Sweden? Where did you get your plants from? I expect the northern adapted triploids would do best for you - unless you know different.......

Good luck

Rhizowen said…
Here's another website that might be of interest to you Axel (and anyone else interested in hopniss):


Clearly "apiosu" is being cultivated as a niche crop and has been promoted on TV. They seem to be selling the tubers - presumably these are from an improved variety.

It would be great to hear from anyone in Japan who has experience of growing, eating or breeding apiosu/hopniss.

They are claiming that apiosu contains 30 times the calcium, 4 times the iron , 5 times the fiber, 6 times the protein, 2.5 times the energy, (calories?) compared to ordinary potatoes as well as vitamin E . It's good for young and old, pregnant women etc - oh no, not another superfood!!!.
Axel said…
Thanks for the answers!
I look around and found a rapport from 1993 written by Hoshikawa, http://mitochon.gs.dna.affrc.go.jp:81/csdb/jc/jc64/64323.pdf could it be the one you reffered to?

I wonder if they, in japan, has any development going about with their native Apios fortunei.
I have also come across some information that the Apios priceana has bigger tubers than A. americana as a average. Is it perhaps that the A. americana is much more common and more suitable for selection of different clones?

My hopniss was collected in Maine, usa, some time back. I got it from a botanical garden, where i work in the summers seasons. It grows well there, almost like a weed (at least in the bed where it grows). I will try to grow my plants in different places to see how it goes. The biggest tubers i have dug out of the soil has been maybe 3-4 cm wide. But those i've seen in picture from the japanese pages haven't been so much bigger.
By the way, the hopniss from my work does set flowers but i haven't seen seedpods on it...
Mark said…
What kind of rhizobium inoculum does Apios need? I remember somewhere I think it said cowpea (this means the Bradyrhizobia group of bacteria). Not sure if such exists in British soil and it needs to be ordered. Any ideas? I need to know as I will be going back to Scotland sometime soon, and would like to get reasonable tubers. Maybe the corerct inoculum might help increase the size of the tubers
Rhizowen said…
Hi Mark

As you have mentioned in some of your other posts, Bradyrhizobium species are required for apios nodulation. As my original plants came as tubers, they were already colonised with what are presumably the right species and they nodulate really well. It's easy enough to pick off some nodules then crush them in some water and pour them on any "virgin" seedlings or tubers that don't have any nodules.
Gabriel said…
I've been reading about it all day today and for sure will try it when the weather warms up.
I'm in a summer dry temperate climate in the Romanian plains.

From what I understand, the dutch tubers should be hardy to at least -25 C right? Pfaf.org lists it as hardy to zone 3

Also been reading about people harvesting it by just pulling the plant up - and the roots come up as pebbles on a string, did you find that to be true?

Thank you, great blog and great roots