My hibiscus survived a couple of "minor" freezes in
2008, but last winter's more intense freezes did them in, entirely. Frankly, I would suspect that most hibiscuses (?hibisci?) will NOT have survived this present spell.
I haven't looked under their blanket, but I assume that my crotons are gone.
Before too long, I expect to get really serious about relandscaping entirely with cold-
and drought-resistant plants! I've just got to feel warmer!
SWR