I suggest looking at these two webpages:

http://daylight44.net/moth.html

http://www3.islandtelecom.com/~oehlkew/zpupae.htm

Thanks KC. I've already read both of those, and they are helpful just kinda contradictory. I guess I'll see how it goes this year and gain experience from it. Thanks again for the info. Cathy

I find overwintering imperials to be a crap shoot. What works wonderfully one year can be a total bust the next year. I have no idea why. Very discouraging. I have found that keeping the dirt buckets inside all winter works out great but the moths will eclose around 6 weeks earlier than the wild ones. Not a good thing if you are trying to attract wild males.

I never mist cocoons and things work out fine. That said, I'm not going to claim that method works fine with prometheas because I have overwintered maybe a handful of them.