I only have three plants. One is 2 ft tall, one is 3ft tall, and another is 8 ft tall. I do need to prune off some of the excess shoots though. Plants grow well early here, but towards the end of summer there is just not enough sunlight.
I ran three lines of twine for each rhizome from the ground to the eaves of the house, which is about 18 ft. Last year none of the plants made it to the eaves, but I think this year it will be a formality. I told my wife that I may need to run more twine this year and she gave me the stare of death.