Answer: There are many types of gardenias and most are hardy in North Carolina. Gardenias thrive in warm areas of the US. They do not tolerate cold below 10 F. If your garden gets that cold, they need to be covered if the temps fall below 15 degrees or so to prevent damage to the foliage. So check to see whether you're growing a gardenia from a nursery or one from a florist. Florist's gardenias are best grown as houseplants.
To repot a gardenia, thoroughly water your plant the day before the move (wet soil clings together, making the unpotting process easier). Then moisten some potting soil and put a few inches in the bottom of the new pot (your goal is to have the gardenia growing at the same soil level as it was growing in the original pot). You can set the potted plant into the new container to see how much more or less potting soil should be placed at the bottom of the new pot. Once you're satisfied with the soil depth, lay your gardenia on its side and pull the nursery pot off the root mass. If it doesn't slide right out, use a thin stick (like a paint stirrer) or a long bladed knife and go around on the inside of the pot to loosen the soil from the sides of the pot. The plant should slide right out. When it does, place it in the new pot and fill in around the sides with more moistened potting soil. When you've finished filling the pot, water the plant thoroughly to help settle the soil.
Enjoy your gardenia!
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