"Kalmia" wrote

Borderline zone 9-10.
Had a week of freezing nights here in January.
Holly bush now has very sparse, curled leaves. What if anything can I
do to bring it back to its old green self?

I think you are too hot for Holly. You have some other issue, not the cold.
Mine was happy with 2ft of snow on it.

Not sure of the answer, but this seems more some sort of disease to me?