Answer: I would suggest you start them now to get plants ready for next spring planting.
Chip the seed coat to break it so moisture can readily enter the seed. This may be done several ways. Many gardeners use a file, pruning snips or sandpaper to break the coat. Next soak seeds for 48 hours in warm water, changing the water after 24 hours. Then plant 1/4 inch deep in a peaty mix and keep warm and moist until they germinate (which may take a month or more).
Have fun with your canna project!
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