Yes, sadly, you need a good long hot summer for good flowering on these, and that's not what we've had this year. Keep the corms somewhere frost free over winter and replant in early spring, putting outside when all risk of frost is past. If we have a better summer next year, you might get good flowering, but usually, their leaves are pretty spectacular anyway if they're the coloured kind.

It was a poor year for them - you're not alone!

Thank you for the info on Cannas, hopefully they will produce flowers next year.