There is at least one relatively hardy species of croton but it's not terribly interesting: Croton alabamensis.

Down here, we only get 2-3 months' worth of weather the crotons can't hang with, so I dig mine and put 'em inside. Leaves drop from stress, but they come back just fine.

I suppose you could conceivably just bury the pots and all, or put 'em in such a way that he pots are concealed.

sea ya
tami

Here is a link that might be useful: my garden pix

Yeah that's what I'm talking about. You just can't find those yellow and orange leaves on any hardy plants. Maybe I will try that.

Actually, some Aucuba cultivars approach crotons in appearance. There is one with a large central yellow blotch that is extremely croton-like. I can't remember the cultivar name but Boca Joe grows it--maybe he'll chime in.

Yes that is my favorite. Hard to find though. Oddly the one called crotonifolia just has a light scattering of yellow spots over the leaf. Must be grown in shade here or will sunburn badly.
Euonamus japonica has some cultivars for sun that have colors approaching orange, but euonamus is very vulnerable to mildews here, so I avoid them.

Hi-
yah John, It's Aucuba japonica PICTURATA- awesome lime green leaves with huge lemon yellow centers, unlike the other aucubas. Perfectly hardy here...

Boca Joe