I grow a number of them - neither of the ones you mention sadly - both in the ground and in pots year round. The only ones I have had trouble with were Chomp and Art Gallery Curly-Q. However, now that Chomp is established and been through 5 or 6 winters, it grows and blooms like a beast.
It may be that the older ones were those he hybridized while they were working on Long Island. I'm not certain when they moved but it is tempting to speculate that is related.
