Canadian Gardening: Question about Cannas, 1 by OldFlowerGirl

OldFlowerGirl wrote:
Lynn, they have always been in a South West Exposure and I know that is why they have grown so tall and healthy, but why no blooms. I don't know what species they are, but they are green with red veins in their enormous leaves. Yes, they are really pretty and tropical looking, but no flowers....

In Trail, which is 15 minutes south of here, I noticed a gorgeous display of Cannas in flower, but they are the dark leaf variety. Could that be the difference?