beesy,
I'm assuming they were first year plants when you took them in the garage. Most likely the warmth of the garage brought them up this early and they probably should be moved to the coldest part of the garage (if not as close to outdoors as you can come) They should have enough reserves stored up buy now to overcome the loss of the premature start which will most likely happen no matter what you do. If you have to grow them in pots I'd just repot them in bigger pots (2-4x) very deep. What you are trying to do is to retard the new growth that will come to allow the temperature to warm to the point where the new growth won't be frosted off. It would be a lot easier if you could plant them into the earth. Sorry but a couple IPA's makes me ramble non-coherently. 'B-hoppy', cuz all will work out!