that's actually pictures of 2 different plant
the first one of the plants emerging in spring is plants put in the ground the previous spring I had purchased as 4" plants from I think wellspring nursery on ebay. They're in raised beds full of compost and had quite a bit of mulch on them that first year. Last years winter was cold as crap around here
The second plant was donated from a neighbor and was about 3 ft tall when I planted it in the spring. The picture really doesn't do it justice, it's from July, by the time late September rolled around it was much larger and quite a sight to behold.
I mulched good that first year but other folks around here with established mats don't do anything and they seem to tolerate winter just fine. I drive by a guy's house every day who overwintered a mat as 5 ft preudostems in his side yard last year and by early May he had 12 ft tall nice looking plants. Really pretty stunning for central NC
The one in that second picture looked to me like it wanted to bloom by the end of last year so kind of expecting that early next year, but it has several pups so it should be fun to watch
check out these pics of a couple of ensete glaucom and 2 alocasia "Borneo Giant" I'm overwintering in my basement
no way those guys can survive outside but they make really spectacular plants ;-)
Index of /ensete
Dave