[beady]

07:

I have experienced that problem in the past growing hybiscus indoors in New England. They would bloom till Christmas, then begin to look very grim. Granted not from frost damage just exhaustion.I would cut them back severely and water them faithfully. Around the end of March they recovered and greened out ,as yours are now. At that point I would feed them with a bloom enhancing fertilizer. I was always rewarded with beautiful blooms for the remainder of the year. I think that will work for you.