I saw this banana tree at the Atlanta Zoo and they are huge. The leaves are taler than I am at almost 6ft. Any ideas?

This is what I currently have trying to do a subtropical garden that looks tropical. I have musa basjoo and thai black but want to thin out basjoo to add musa valintina or whatever this tall treei is at the zoo. These plants are about 7 years old but I move them around as needed or trade for other plants.