Originally Posted by Gabe15

Banana roots prune themselves, they only remain active for about 4 months in the ground (probably longer in a container, but the concept is still there) before being replaced with new growth, so to control the size of the root system it is best to do exactly what you have done and just limit how much soil it can grow in.

I tried this with a 'Little Prince'. The plant in this photo is almost 3 years old in an 8in pot and has about an 8in pseudostem.