I noticed that my rosemary was hanging in there too. It’s only under on layer of row cover. If it survives, it will be the first one to make it through Mo. winter.
To overwinter rosemary is a cinch. HEAVY mulch. Extra water on warm days (not freezing ones, duh!). Cover entire plant with a light bedsheet when temps are below freezing, anchor with a couple of bricks or rocks. It is better generally to UNDERdo rather than even come close to OVERdoing water until March/April (in Missouri).
Best possible case (outside) is an elevated bed to prevent even accidental freezing of the roots. 4-10 inches is sufficient.
I'm going to have to look into this raising dill hydroponically. Also, there are a couple-three sage seedlings this year. Found out what killed the sage/salvia last time, will NOT repeat even the possibility of that error!
Smooches and FReegards!