Impossible to tell with the information provided. Most gardenias are not reliably hardy in Tennessee (at least many parts), but some are (even in colder parts of TN with the right condtions). If we knew what type of gardenia it was (species or cultivar or whatever) and where you were (nearest large city, so we'd have a good idea of your climate), we might be able to give you a guess.

Was there a tag on the plant when it was given to you? If you can get a cultivar name (if it exists) and where you live, we can tell you whether it will be hardy outside. Without this info, it may be difficult. I can tell you that many of the hardy varieties often have smaller leaves in comparison to the tropical varieties.

He grew it from a cutting he took from a gardenia he planted in his yard some 30 years ago.. It was a plant that was given in memory of his brother who died at birth and the original plant is on the family old home place in Kenly, NC. He said I can keep it outside, but I am so afraid of losing it... Maye if I keep it sort of under cover at least...

Thanks
Carolyn

I think you'll be fine. Just make sure to plant it near your house on the south side just to be safe.