My corms do get bigger but quite slow. I keep some of the pots outside while it is very warm with nights at 74F, days 85F. And bring them in while it is still about 65-ish at night. I read long time ago that they will only grow when soil temps are above 65F. So naturally if they are in ground they might not survive even in central FL when exposed to damp/cool conditions.
But some very large varieties i keep strictly indoors with part sun from E/W. Still most of my varieties go dormant with less, weaker sun in the fall.
I overwinter them dry in pots (temps not lower then 65F).
But one that i kept in South FL indoors year round in steady 73-76F temps (Mrs Halderman) kept going for a record 15 months! It dried up a bit and dropped half the leaves by the end of summer, but then restarted again and kept going thru winter and all of spring. My guess it might be due to stronger light and humidity year round, but also due to the age of the corms: quite large and old. Mrs Halderman is an old large variety. But may be the fact that it got semi-dry rest for a few weeks helped too?
It is waking up right now indoors (after 6 month rest).
I had a C. Creamsicle that is also large and was in South FL too, but it totally went bust over winter, the corms dry-rotted in the pot: it was part time outside, so may be molds got in.
But i also sometimes get dry-rot overwinter in indoors pots, especially with smaller corms. Perhaps a fungicide drench would help at the end of season prior to drying them up.
So it is a hit and miss depending on variety/age/size, but the high temps and high light levels are the most important.
