Cassie's got a point. Mine are up 12-14 feet tall. Also, Blue Javas are extreme heat lovers. We had 7 consecutive days in the 100's this summer & my Blue Javas loved it.
Not sure what the weather is like in the UK, but ya might wanna check out more cold-hardy nanners that like humidity.
Of course, if youre as crazy as me, you'll try Blue Javas anyway! I totally Luv a challenge (no matter How ludicrous
) !
Oh, one caution, nanners do not like sea salt so, if ya live near a shoreline, might wanna re-do the soil to reduce salt content.