I was wondering if you keep your tropicals in a greenhouse over winter. I wanted to share with you something I learned the hard way. I put most of my tropicals in the green house, which was huge, and heated enough to keep the terrestrial plants from freezing, but did not have heaters in the lily tanks...which were also very large tanks.
I lost almost every tropical lily...except those that had a good, hard tuber...which did come back from the tuber...but the tropicals I left outside in the big tanks in full sun, came back much better and most didn't die completely back. Since some of the lilies were new (in the green house) and didn't have a tuber....I lost all of those.
I am not sure where Thibideaux, Louisiana is located, but I'd imagine, south Louisiana. I live near Galveston, Texas, so our climates are probably similar.
Anyway, after that, I no longer kept lilies inside over the winter. Of course, it can probably depend on how much cold we get....all winters aren't the same. Some years we get a lot more freezing temperatures and some years, scarcely a frost, but the outside tanks warmed up much better than the tanks in the greenhouse. If I ever kept lilies in the greenhouse again, I'd probably put heaters in the tanks.