Each year, we plant rosemary, and sooner or later a hard frost always kills it off.  So this year I've experimented with leaving a cold frame over part of the herb garden  (essentially, a cold frame is an angled window pane on bottom-less box).

This mild winter wouldn't have killed off the rosemary yet in any case.  It's only fallen into single digits a few times and never for very long.  Still, the rosemary does look happy in its little greenhouse - as do the oregano and parsley.  Only the thyme seems indifferent.

And Haru would like a greenhouse of his own.

_