Cannas Stuttgart and Pretoria

Hi, I love a Canna and I’ve recently bought Stuttgart and Pretoria.  They’ve both sprouted a leaf which is great. Just wondering if any one else has grown them? How big they get? Have you grown them in the ground or in a pot?  My other cannas are Wyoming and a yellow one with a speckled throat, both of which are in pots. The sad little one in the photo is Tropicana but it never seems to get past this stage. It’s already been repotted this spring to try and get it to grow
Thanks