I grow most of my LA's in ground, but I do have some in large pots and tubs. A lot of vendors grow them in very large tubs. The reason is that LA rhizomes "Walk". The rhizomes grow very long and so the the increases growing out from the mother grow pretty far away, and their increases stretch even further. I do find that some have made it from one side of the iris bed to the other so it is a pain in the butt to sort them when I lift them for a bed redo. The tubs keep the rhizomes contained and it's also easier to keep them very wet. They love the wet but mine in ground have survived just fine even when the soil dries out. And btw - if you trim pieces off the rhizomes while planting/replanting keep track of those cut off bits. Squirrels got into mine and I had LA's sprouting up all over in the grass. How? Well, LA's are well suited to survive. You can cut up a rhizome into pieces and each and every piece will sprout roots and grow. No fan end needed. Crazy things. Love em.
