OK, so I've admired canna lilies for years, but I've been scared off planting them because they must be dug up in my area (south-central PA). But I can't resist. I'm thinking of trying cannas in some large planters I have - about 32" diameter, 42" tall - old crocks with drainage holes. I've grown hisbiscus "trees" in these before, but I love the idea of canna lilies instead.

So my questions: can I start the tubers in medium pots in my unheated greenhouse now, to plant in the larger containers in early May? Or should I start them inside my heated house? Then how many tubers can I put in a container this size (again about 32" diameter and quite deep)? Any suggestions for varieties that are easy to grow for a newbie? I'm partial to reds and oranges with great foliage. Thanks so much for any help you can give me for my new canna obsession.