I had a great hisbiscus plant. We had a cold winter this year in Southern GA. It is now just brown. I am not sure if it dead and have to start all over.
Certified GKH Gardening Expert
As long as the stems are still alive (pliable), it will come back. This article will help you with caring for it with the damage: https://www.gardeningknowhow.com/plant-problems/environmental/tips-for-saving-cold-damaged-plants.htm
This article may also help you in determining whether the plant is still alive: https://www.gardeningknowhow.com/plant-problems/environmental/how-to-tell-if-a-plant-is-dead-and-how-to-recover-an-almost-dead-plant.htm