I am keen to experiment with novel tuber crops, but am struggling to find where I could get tubers or seed for most. I have Jerusalem artichokes already, and should be able to obtain Yacon and Chinese artichokes from Koanga (though if there's a Canterbury source that would be great). But I'd like to try out everything I can to see what grows best in our climate, we've got a lot of frost and I'd like to see what can cope with it.
I believe these are already in the country, but can't find a source for them:
Mashua - Similar to Oca ("yams"), but probably more tolerant of difficult climates
Ulluco ("Earth Gems")
Chinese yam / Nagaimo (Dioscoria polystachya / opposita / oppositifolia)
I'm not sure if these are in NZ:
American groundnut (Apios americana)
If anyone knows where I could obtain propagation material for any of these, or any other novel tuber crops I may have not thought of, ideally in Canterbury, that would be much appreciated.