unless you want to transplant every year, frenchy, i would just do one or two at the very most. i planted one, in a 20 gal. container (8/2016) two years ago, and i will need to thin and divide for sure this year. rhizomes in my area grow rapidly; if there's time today or tomorrow, i'll take some pictures of the rhizomes in the pots, already crawling on top of each other........i will post separately, so you won't have to look up this particular post again.