I believe we are in zone 8.
How to Winter a Three Foot Plus Hibiscus That Is Growing Outside in MS
Certified GKH Gardening Expert
If it is a hardy hibiscus, than it needs no winter protection. If it is a tropical hibiscus, it is iffy if you can winter it outside in your area, but it is worth a shot. Mulch the roots heavily and wrap the plant in chicken wire (or something similar). Fill this with leaves or straw. Then wrap with burlap, leave the top open. Remove the wrap and mulch in early spring.