an attached garage is usually a zone or two warmer ..

ken

Unfortunately I don't have a garage, or else I'd put it in there. I thought about stuffing it in the crawlspace under our apartment, but then it would get absolutely no sun at all.

Do you have a sliding glass door? If it has drapes, you might try putting the gardenia pot between the cool glass and a thermal or heavy drape to keep a cool, bright zone for your plant during the winter months. Gardenias make good house plants if they have a bright, cool, spot and sit on a tray of moist gravel for humidity.
Another idea would be to use a clear, large tote container as a mini greenhouse on a balcony or patio. I read recently that a string of holiday lights can keep a plant a bit warmer, and you could use that idea in with the mini greenhouse. I hope you find something that works for you.

Not to throw a wet blanket on your plans, but if you're going to have a potted Gardenia, better to grow one of the tender cultivars that blooms all summer with big flowers than Kleim's Hardy, which blooms once in early summer with relatively small flowers.
Digging it up every winter isn't going to be feasible really, it isn't the kind of plant that would cotton to that. It's either in the ground year round, or in a pot year round. Sorry. The good news is if you have a string of mild winters and a sheltered spot in should be ok in Louisville, at least until another winter like this one.

BTW sheltered means near a building or fence, with protection from winter _morning_ sun. That is what kills tender broad leaved evergreens in zn 6 & 7.
MIne never had a lick of damage until this winter, which killed it to the ground but it is vigorously resprouting. My prior low had been 7F and this winter it was 3F, 3 times.

This post was edited by davidrt28 on Tue, Sep 9, 14 at 16:21

My gardenia was a free gift when I ordered a honeysuckle from an online grower, which is why I have it at all. It was so cute when I got it (just 4 little leaves and an inch tall!). I just had to keep it like it's my baby or something.

I do have a west facing patio though, surrounded by a short privacy fence. It would get maybe 3-4 hours of sun there in the afternoon. Would it be better to just leave it out there next to the window then? I'm not sure I could find a clear container big enough to cover the entire pot (it's a 20" pot, so the gardenia would have room to grow into it). This summer I've been moving the pot between the middle of the garden when it's dry out so it can get a full day's sun, and under the eaves when it's rainy so it doesn't get too wet, cause I know they're picky about soil moisture. It always looks sad when it's been under the eaves for several days and so not getting much sun, and perks right back up when it's in the middle of the garden. I don't want to kill it with too little sun in my attempt to keep it warm.

I might try the Christmas light idea on very cold nights. I'm just hoping we don't have another crazy cold winter like this last one!

"I do have a west facing patio though, surrounded by a short privacy fence. It would get maybe 3-4 hours of sun there in the afternoon. Would it be better to just leave it out there next to the window then?"

Sounds like a very good spot for it. But remember, if we have another really bad winter, it will die. AND, it's too late to plant it for this year anyhow. Tender shrubs in borderline areas need to be planted in the spring.