how long is a piece of string???? who knows i think you have just gotta find out

but i believe that there is a few things 2 help it get taller as such, such as (i never knew this but sounds interesting) the deeper the whole, the taller the plant will become........the roots will get longer, and i guess just look after it, plenty of water and nutrients will make it grow nice and healthy (stress free) which MAY cause it 2 grow just that lil bit taller, and as well as the hours of sunlight.......if its got plenty each day and lots of fresh air.......then no need to worry

personailly sp?.........if i had a 7 foot plant........i would be happy cuz that will more than likely bud loadz.