I'd say 12 inches in diameter as an absolute minimum, but bigger would be better, especially when it goes out onto the patio next summer. If you're going to have it inside over the winter, put it in the brightest possible location.

I grow my Wyoming in a 12" pot (top diameter" that I buy at Wallmart). My Wyoming canna loves it's warm environment in Florida, and I feed it Miracle Grow Bloom Booster.

Thanks, all!

Responding to the rain, my four clumps of Canna 'Britannia' all decided to open their first flowers for the season. They are all in different micro climates in the garden and different soil types as well. I thought you might like to see the cheery face of this young division.
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oliviaharis

Wyoming Treatment Centers