This is the first time my neighbor and I have grown a canna and it was supposed to be a dwarf. As you can see it's NOT small! Our question is do the individual flowers fade after a day? They're only open for a day and then they shrivel up and look ugly. We have three stalks out of many that are producing flowers. We were hoping for more! Any comments, suggestions, ideas are welcome.
In my experience, my canna blooms rarely last more than a day. I thought the ratty appearance was due to hummingbirds visiting the blooms but perhaps that is normal. There will only be one bloom on a bloom stalk and it is recommended to cut that stalk down after blooming. It will regrow and bloom again. I am afraid it may not be suitable for a blooming container setting even though it has pretty foliage. I suspect you wanted more blooms.
But then, maybe someone else will weigh in with more experience on this.
I dug my dwarf yellow cannas last summer when we were so dry and put them in a container. They have grown taller than they were in ground. I believe that is due to the better soil/water conditions they are now receiving. Perhaps that is why yours are taller also.