Pamela, your Caladiums would be prettier if you had them all in one pot - they look better in multi-bulb settings. The pot size you have each one in would be big enough for all three. I think I have about 10 bulbs in a 12 inch pot.
The best way to overwinter Caladiums for those of us who don't live in Florida (Hi Elaine
) is to dump them out of the pot and store them in a cool place (bare root) in damp sawdust or newspaper (operative word 'damp'). In the spring, you can plant them up and enjoy them for the summer.
If you are lazy (like me), leave them in the pot and store it someplace cool. Keep them BARELY damp. You don't want them to dehydrate but you don't want them to rot either. I water mine at the end of summer as they start to go dormant and that's it until spring.
As you just potted them up, I would unpot them and wrap them up and store them away in the produce drawer for the winter. Wet the bulbs and wrap them loosely in newspaper then in a plastic grocery bag. Leave the bag open so the moisture doesn't build up but just open enough to allow for respiration. Check on them periodically to make sure they aren't dehydrating or rotting.
That is a really pretty leaf pattern. Mine are mostly red with a small amount of green. It was supposed to be a mixed bag but it was a mixed bag of red with a little green.