I grew it, and it did well, producing some huge roots (up to 1'
long and 6" thick); this was on sandy soil in (dryish for the UK)
Cambridge. However, it is very frost-sensitive and so a b*gg*r for
me to overwinter. But the real problem is that I found it useless.

Its roots are not for energy storage, so much as water storage, and
are an extremely pleasant, sweetish, crunchy vegetable in salads.
That would be fine, except that they mature in the autumn and are
so frost-sensitive. My wife didn't like it much, because of its
slight taste of raw Jerusalem artichoke (surprise, surprise). The
roots are also extremely brittle and VERY hard to dig up intact.


Regards,
Nick Maclaren.