Mark, I wait until the leaves die down and the stem look really bad. This allows the plant to build up as much tuber mass as possible. I usually harvest the tubers in early December. They will remain nice and plump for a few months with the rain but will start to shrivel if you don't give them enough moisture. I pick out the seed tubers for the following year and plant those into a well drained mix of peat and perlite and keep them outside (not freezing). They get watered occasionally to keep the peat moist. The tubers will stay in dormancy in the moist peat until the growing season when I take them out of their peat home and plant them in the ground (or large buckets). Roland, when you said you bury the stem, do you mean you treat them as if you were growing potatoes? Nhu On Fri, Nov 11, 2011 at 11:36 PM, Bulborum Botanicum <bulborum@gmail.com>wrote: > Mark > > the later the better > And I buried most of the stem for a larger harvest of tubers > > I harvested them just for the frost (here half or end December) > where I lived in Holland they where not hardy > I did not try to grow them here in France > > Roland > >