[surbie100]

Yes they are, not that I knew that before Googling today! 

[Madame Cholet]

Just bought some seeds too.

[strangerachael]

Am growing these too for the first time this year.
Interesting to see that they can be treated like a perennial and lifted & stored over winter. Anyone had any success with that?

haven't tried but did notice their big juicy tubers when I pulled the plants up, and wondered whether they could be eaten? I wouldn't bother storing as I still have plenty of seeds and would guess you could save seeds too.