Q.Crotons
Crotons were covered during freezing weather. Have lost all leaves. Should I cut them back now or in spring and will they come back?

It is likely that they will, but you are right on the fine line on where they can survive. I believe that covering them will help. I would wait until the weather warms up to trim them, though. Here is an article that will give you more information: https://www.gardeningknowhow.com/houseplants/croton/growing-croton-outdoors.htm