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OK, we need more from you. Firstly where in the world is it growing? Can you tell us how big those tubers are? And can you provide a larger picture where we can see the detail?

Meantime - is there any reason to suppose it isn't a very healthy potato?

OK is not a potato and it's not a dahlia. But we still don't have a clue where on the planet this thing is growing. That information would really help. And is there any top growth to be seen?

One presumes California (due to the forum placement), but that's a large variable area.

Good thinking. Didn't clock that.

This is California, bay area, San Francisco area :) zone 9b

Krishi I think you should move this to the Name That Plant Forum.