I've grown them all Evan! I had some supposedly more reliable named varieties of Z. aethiopica, namely Pink Mist and Mr. Martin. They did OK while I kept them in pots over winter, and while we had relatively mild winters/springs and relatively 'warm' summers, they would start to grow in the greenhouse in late winter although I didn't get many flowers and sometimes none. I started with 'Crowborough' planted in the ground, the tubers grew a little but the foliage struggled to make anything other than a couple of small leaves, so after a few years I put it in pots. I was lucky to get some flowers in a greenhouse when the winter/spring was mild.
Then came very cold springs and summers, that's when they really started to struggle. Eventually they fizzled out due to the inability to grow enough to sustain the tuberous roots but when they were growing well I had to keep dividing them, although Mr. Martin was really the only robust one.
I had the same success or better with the Calla hybrids, some grew huge tubers and multiplied like wildfire. I kept them in pots in a greenhouse over winter where they survived, it's possible if I had lifted them to bring inside and replant in spring they might have continued doing well but a run of cold summers seemed to be what finished them off.
None of them would survive in the ground here, we just don't get enough warmth and often too much wet. I'm certain if I had some in pots in a greenhouse during the very harsh winter 2010/11 they wouldn't have survived. It was great while I got results, too much work to keep trying otherwise.
