How to start yams from a tuber

I'm not talking sweet potatoes.  Or at least I'm pretty sure I'm not.  The organic store near me has several kinds of sweet potatoes and one thing they call "yams".  They grew well for me in the past but I struggle to get slips from them.  I've tried cutting them in half and setting them in water.  I've tried partially burying them in damp potting soil.  I'm out of homegrown ones so I just picked up a yam from the store.  I'm going to try the toothpicks in the glass of water (uncut full yam) unless there's another way I don't know of?

Any other techniques?

Thanks!

True yams are from the dioscorea genus. They look very different from sweet potatoes. They’re oddly shaped and their skin is rough. They can have stubborn dormancy and hate the cool even more than sweet potatoes do (except for the hardy species).

I found “ratalu” purple yam at a local Indian store. I think this is synonymous with what Filipinos call Ube, which I believe is the species Dioscorea alata.

Getting them to break dormancy is an enigma to me. I think that ultimately they will do so on their own terms. They seem to want to be hot and humid, but definitely not wet. Finding the sweet spot in terms of moisture was difficult for me. They will rot if soaked for too long, and perhaps shouldn’t be soaked at all.

Mine started sprouting after the following procedure. I soaked them in water overnight (<12hrs). As soon as I took them out of the bucket of water, I dabbed them off and put them under a strong fan to dry their exterior. My thought process was to rehydrate them but prevent mold from forming. Then, after I thought their skins had thoroughly dried, I wrapped them in towels (intended to moderate the humidity from becoming too excessive) such that they were not touching each other and were completely surrounded by the towel. Then, I took the whole wad of towel-encased yams and put it in a single plastic grocery bag, loosely-tied, and placed it in a warm-ish location. Within a few days, I could see little round nubs starting to protrude from their rough, brown skin. When they emerged, the new growth was a beautiful bright purple.

Unfortunately, many of them also started growing a white mold on the outside surface. I freaked out about the mold and over treated them with elemental sulfur, which I think set them back. In hindsight, I probably should have tried gently blasting it off with water from the hose and/or treating with H2O2. Heck, maybe I could’ve just ignored the mold and just planted them as is. It’s hard to say.

It’s unclear whether anything I did induced their breaking dormancy. They may have done it without any intervention on my part.

They bounced back from the sulfur treatment and are currently doing well. I think I got lucky with the timing of them breaking dormancy which corresponded well with our weather warming up. In my Pennsylvania climate, I doubt they’ll be anything more than a curiosity and an ornamental.

Despite all of the finicking I did with these, I recently discovered a hunk of yam that I had thought was rotten and subsequently disposed of on the ground, completely forgetting about it. That was weeks ago. Just a couple days ago, I discovered that it had put down roots through the lawn and is growing without any special treatment whatsoever. What gives?

I’m hoping to be able to bring some of these inside and sustain as houseplants through the winter. The foliage alone is really pretty.

I didn’t have much luck finding any literature on this topic with clear answers or instructions. If anyone can provide any, I’d appreciate it. I figured I’d just experiment with them and thankfully I was successful at at least not killing them.

Also, David the Good has a lot of information on yams on his YouTube and blog.

Best of luck.

I think you may want to try planting them from an aerial tuber, the tiny round tubers they make from their aerial parts. I got mine from Strictly Medicinal Seeds—six aerial tubers, and one yam came from them. The yam is now maybe four years old, and flowering for the first time. I have not dug up the root, as they take a while to form and I want the yam to reproduce as much as possible. They form aerial tubers in the axils of leaves on the upper parts of the plant.

I've bought yams at the International grocery store and started them You don't want to put them in water to root. I was told to cut them in pieces, dust the cut parts with ash and then plant them. David the Good has lots of information on growing them https://thesurvivalgardener.com/?s=yams

and I highly recommend his videos.

https://odysee.com/@davidthegood:8/why-are-true-yams-such-an-incredible:3

Last year I bought two bulbils from Etsy and both sprouted. I grew them in a container and their roots were restricted and couldn't reach full size. Nevertheless, I ended up with tubers larger than my fist. They were just left on the counter indoors for 6 months. I thought about cutting them into pieces to taste test and planting the rest like potatoes. I instead planted them whole this year, worrying about moldy wounds.  I didn't know the tubers are hardy in ground in zone 5 as M Ljin mentioned.

Aerial tubers aren’t always easy to source. I’ve bought some from Interwoven Permaculture Nursery and Daisy/David the Good’s Etsy shop.

The only species that I’m aware of that are cold hardy are: polystachya and japonica, with the former being hardier than the latter.

Jonathan de Revonah wrote:Aerial tubers aren’t always easy to source. I’ve bought some from Interwoven Permaculture Nursery and Daisy/David the Good’s Etsy shop.

The only species that I’m aware of that are cold hardy are: polystachya and japonica, with the former being hardier than the latter.

Mine are polystachya for reference…

I store my tubers for eating in a plastic bag alongside my potatoes, in a cool kitchen cupboard. I found my last one sprouting about a month ago (in July), so potted it up. It's probably Dioscorea polystachya, obtained from a friend  who probably got it from Real Seeds in Wales (RealSeeds). It produces a few sub-pea size aerial tubers, I haven't seen flowers.
My technique: start the tubers in tall pots, after frost place well-sprouted plants on a bin of potting compost located under a tree with handy dangling bits to give them a start into the canopy. Slugs like them, so give them nothing to climb up. Before really cold weather starts, lift them: what's in the bin is profit, we hope; what's in the pots is for next year. So check there is tuber in there - it may have given its all to dive deep, in which case put some tuber in. The pots and tubers for eating come indoors. I don't start watering until Spring.