Karen and Cindy - Thank you.
Greg - Even living in zone 9b/10a, I get paranoid each Winter. (We've had Winters that were very cold for our zone.) I tend to cover my daylily beds with sheets on the coldest nights. (Some of my tropical plants do get frost burn.) I see mine putting on new growth and don't want a cold night or two to harm that growth. But even with that, I still lose a few of my daylilies every year. I always assumed they were daylilies that were on the "dormant" side. Though now, I am wondering if I over-hybridized such young plants or they developed root rot or some other malady.
It seems no matter where you live .... daylilies aren't always the tough suvivors as I once thought.