The stalks are terminal, meaning that once they flower, that is it. However, you can cut the whole stalk at the ground and another will pop up and bloom again.

In experimenting with my canna after blooming and seed pods are dark and ugly, I have cut off top and and found in a couple of weeks another blossom happening. It doesn't work all the time though. Don't really know why or the circumstances that prevAIL, BUT HAVE BEEN PLEASANTLY SURPRISED by this.

I always cut the seed pods off- plants spend so much unnecessary energy on them. And I too have been pleasantly surprised by extra blooms :)

Here in the Dallas area, many of us who have beds just chop them all down to ground level when they are through blooming. We have a long enough season that if you fertilize and water them they come back up, looking better and bloom again. Mine are in pots and I always cut the bloomed out stems down to ground level. Keeps the pot neat and makes room for another one to come up and bloom. Learned to do that on this forum and it works well indeed. However for many beds that would be pretty darn difficult if not impossible, so chop shop for them. Betsy

I'd suggest to collect the seeds. Canna are fairly easy to grow from seeds. Even if you don't plan on growing them from seeds you might have freinds who might want some of your plants. Plus canna seeds are very pretty. A good reminder to past grwoing seasons..

I'm a chop to the ground kind of guy, if you have a long growing season like you should in zone 8.