Q.How Do You Prepare And Store Canna Bulbs?
First time grower of Cannas. learned that I planted (in container) too many bulbs. Beautiful and very tall foliage but no flowers.

Certified GKH Gardening Expert
Typically, you would just cut the tops off and move them into a safe area to "sleep" for the winter. Since yours may be overcrowded you may need to separate them and store them differently. This article will help:
https://www.gardeningknowhow.com/ornamental/bulbs/canna/storing-canna-bulbs.htm
Here are more articles that will help you:
https://www.gardeningknowhow.com/ornamental/bulbs/canna/planting-cannas-in-pots.htm