They will have to be covered when you expect a freeze. Go to the Gooodwill and get some light weight blankets or sheets. I have three and even tho' I live in zone 9 there is always a chance of needing to cover mine in winter frosts.

The strategy Sherry describes, Kimberlee, will get a hibiscus through a light frost. It will not get them through the kind of winter temperatures I expect you get in Zone 7b. If you ever have temperatures below the mid-20s, you are likely to lose your plant if it is outside. If you want to take your chances, be prepared to run Christmas lights (not the new LEDs, but the old-fashioned bulb kind) around your plant, turn them on, then wrap the plant in several layers of heavy frost cloth. If ...»

I have 8 large ones in pots and always bring them in during the winter. It's a lot of trouble but the beauty of it is that they bloom all winter and what a beautiful sight to see gorgeous hibiscus blooms in January!

If you prune them back by 25% they might be small enough to make the move indoors without a big problem....but they DO need lots of light indoors in winter.

I have the "tropical" ones too...in huge pots and bring inside for winter. If left inside in warmth, they will bloom through Christmas...then I cut back. If inside in lower light..the garage..I cut back in Oct. ..but they're fine until spring. Spray well before bringing inside..they tend to magically produce aphids once inside.

Even adding a couple of lights to the room where you end up keeping your hibiscus will help, Kimberlee. Since it is the total amount of light the plants receive that counts, you can leave the lights on 24 hours a day if that doesn't drive you crazy.

We live in Dunwoody which is the same zone and we built a makeshift green house on the back screen porch last year using a metal shelving unit, wrapping it in sheets when it was cold and putting a spotlight inside at the bottom for heat. We would unwrap it when weather was warm and cover it when needed. Nothing of ours died. My son is a plant freak so he took the time to do this regularly!