In 1996 I purchased 5 of these. They grew fine for 3 years in the shade but then all but 2 died off. The surviving ones I left there. They spread to a good mass, enough to devide. I devided then to singles and planted in many spots. It seems they aren't very fussy or at least tolerated various conditions. I have them in a full sun garden, under a pine tree and in shade next to the house. the ones in full sun are a bit shorter but flower ok. The shaded ones grow to 7 feet for me. My opinion is they like a moist to damp soil but will grow else where. However I do need to water the ones in the full sun a lot.Generally they seem to be like bearded Irises in that they prefer certain conditions but survive and bloom elsewhere. I have a Siberian Iris which I found growing wild in a foot of water in a river. I plant some in the dry-full sun garden and they grow andspread fine.