Not true

Caladiums do fine in the ground, and mine even survived 24' of salty water...

sea ya
tami

Here in So LA they do a little better and last longer if you take them up and let them ripen in the fall, and store for a few months. I was told that and didn't get around to it, and they came back the next year but not as many, and then the year after that there were a few small ones. Maybe this year I'll dig 'em. Maybe.

I am also in South Louisiana Z9. Most, but not all, do come back the next year but are always smaller and eventually just fade away. I would recommend digging them up each year and storing properly with fungicide and all that stuff. There are many sites that detail the proper procedure so I won't go into that here. Our rule is to plant them in April each year.

Here is a link that might be useful: Personal Garden Logs

I thought about this post when I was watching Louis Miller talk about caladiums from Baton Rouge today. It occurred to me the difference with keeping caladiums in the ground here as opposed to Florida might be soil type. My understanding is soils in Florida are sandy--maybe not all, but most, right? Our soils are mostly very heavy clay. The drainage in winter, in Florida, and lack of it here, would have a lot to do with how well they over-wintered I'm sure.