Yes, it is deciduous, and yes, I have some growing, in fact, just for the foliage, because four years to get one good root
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I do dig one from time to time,(they're a bit spread around in my garden), and mostly bake chips out of these roots, they're better than potato chips. It's in fact a very easy to grow plant, over her small plants pop up every year, the bulbils can be eaten as well (but you saw their size....)