Eric I was pleased to see you would be around on the forums this week. I shot you an email about air potato and haven't got a response but I think this is a topic worth discussing here because a few other threads have popped up about it with little answers. This would normally probably be more appropriate for the plants forum but I think your write up on this plant and you being around this week makes this an exception.
Is there anywhere in the US that edible air potato can be obtained? The huge write up in your book is one of the biggest teases in the world. A plant with so much potential for ecological starchy food cannot be found anywhere. You seem to be the expert on this plant. Would you care to share any more info about air potato or places it is being grown? I feel many people on this forum would love to be growing it but cannot find it. Perhaps out of this thread a new network of permies sharing D. bulbifera could be born and a new sustainable food source could be much more available. I am currently growing D. Alata and Chinese Mountain Yam but the poisonous air potato thriving everywhere near me is a daily reminder that the edible kind cannot be found! How aggravating! The internet has very conflicting info about this plant in general. Mind clearing this up for all of us in the southeast?
Hi Josh, I'm sorry to say I've been so busy with permies this week that I've not gotten to my e-mail. I often get requests for sources for edible air potato. I'm afraid I have to respond them all in the same way: air potato is illegal to grow or sell in the United States. With that said, yes there are people who grow it and I hope you bump into them. Some of them are in Florida. For those of you outside the United States, Las Canadas in Mexico has a wonderful nursery specializing in useful plants and they sell an edible clone of air potato. They cannot ship it to the United States. The USDA used to maintain a collection of elite air potato varieties in Puerto Rico, but got rid of all of them as well as the rest of their Dioscorea yam collection due to concerns over invasiveness. I think this was a major mistake as this genus is a major world food resource.
Air potato has a poisonous, extremely aggressive form as well as edible, better–behaved varieties. The poisonous form is a global weed and makes quite a nuisance of itself. The best thing I can say if you live somewhere where there is a lot of the poison form is that you should gather the tubers to make ethanol, bioplastics, or some other processed non-food product.
The edible forms of air potato are, again, quite a bit less aggressive. The shape of the aerial tubers varies enormously, reflecting the great genetic diversity that comes from having an native range that stretches from Africa to Australia. Some forms are slightly bitter while others are quite wonderful. What is phenomenal and virtually unique about this crop is that it makes very large amounts of tubers on the vine meaning it is a no–till perennial staple crop which can be stored for months. Productivity can be very high, as much as 19 metric tons per year, which is about the same as the global average for potatoes.
I would refer permies to Frank Martin's Tropical Yams and Their Potential, a detailed look at the genus Dioscorea. It is a USDA publication and can be tracked down through many libraries, though I hope to scan it and put it up on my website soon. Virtually everything you can find on the web about air potato is about how to kill it. I'm doing my best to tout the carbon–sequestering benefits of this absolutely unbelievably fascinating species. Even if it were only to be grown in its native range, the best forms of this species should be widely spread and cultivated as part of a coordinated effort to slow climate change.
Once again, the wild weedy form is very different and much more aggressive than the cultivated varieties. There are other species where this is also the case, for example the cultivated and sterile crop chufa is a form of the global weed yellow nut sedge.
I think we need to advocate to remove the ban on cultivating air potato (and certain other useful “invasive” species), in controlled experiments. When compared with the ecological cost of our current form of industrial food production, the ecological cost of growing non-–aggressive varieties of air potato doesn't look so bad to me. Of course we want to begin with growing the native species of a given area. The best native tuber crop in Florida is probably the groundnut, of which improved varieties are available from several nurseries including Oikos Tree Crops. Florida is also home to some other interesting native root crop species like spurge nettle (stings!) and Florida betony. However, all of those species require tillage for harvest and are thus inferior to air potato in terms of low maintenance and carbon sequestration. Some of the other Dioscorea species also produce aerial tubers, though none as heavily as air potato to my knowledge.
That is a tad discouraging but I have hope I will find it somehow. One problem is that lots of people on ebay and such advertise that the type they are selling is edible but when you message them they say they just picked wild ones in FL. Great way to poison someone huh?
I heard someone grows it in Orlando but that is a pretty broad clue haha. I would gladly drive to Orlando and pay this person lots.
I offer up a lament for my barren fences!
posted 7 years ago
I am very curious about D. alata for bulbil production. I have about 50 plants growing. I am going to try to weigh the bulbils from some plants and compare it to the weight of the underground tuber from one year's growth. Perhaps D. alata could be grown for a few years for above ground production and then harvested for the underground tuber once it is 20 pounds or something.
I have two varieties to work with. One was given to me this spring and the underground tubers are a deep purple. The other I recently found naturalized while walking along the railroad tracks in my town. I harvested one and made french fries. This naturalized type is white on the inside. Not bad at all. I am not digging any more up until I see how many bulbils they produce. Maybe one variety would be better for above ground bulbils and can suffice as a no-till staple until the real thing is available.
I will shoot you the numbers on bulbil weight in the fall.