I can not say if it is eatable or not. I have not eaten it or even thought about it. I may have to look into that also. But I grow it. There is two types around mine came from Jeffersons' Monticello in Va, and is extremely fragrant. Mine is perenial here in SC. even this past year with on three seperate occasions temperatures dropped to the upper teens and I have no mulch on mine but they came thru. I still have about a dozen plants if anyone is interested they came E-mail me. But it roots very easily from stem cuttings take in July on mature vines.
I have not messed with the root, it does not appear to divide by the root because mine comes up from the same main tuber each year so it is not evasive. Mine also produceds viable seeds late in the fall. Seedlings planted this year will bloom mid Aug till frost. Next year the plant will emerge for those in zone 7B or warmer in late April and will start blooming in June till frost. Each year the tuber gets bigger and sends out more vines. Mine is 3 years old came out about 3 weeks ago and already it is near the top of the arbor a good 7ft and about 12 vines from the one tuber and it has some flower buds starting so will be on time to start blooming in June. This is an outstanding vine. I first saw this at Monticello several years ago and from 20ft away the aroma filled the air. Rodger