I'm confused. Do you mean 'CALLA' lilies or 'CANNA' which is something else
entirely?
Calla lilies are properly called 'Zantedeschia' and the other is Canna
indica though there are many varieties of each, 'indica' being the more
common one.
Canna is tender though it can survive outdoors in a sheltered spot as mine
have the last few years.
Zantedeschia 'aethiopica' is the hardiest of the calla lilies and can
withstand several degrees of frost but the other varieties are best wintered
under cover.
Hope this helps.