Answer: According to your zip code, you are gardening in zone 5B or the warmer part of zone 5. However, Gardenia jasminoides 'Aimee' or "First Love" is only considered winter hardy to zone 8 and would not survive your cold winter weather. So you will definitely need to keep it as a container plant so you can easily bring it inside each winter. As far as pruning goes, I would wait until after it has bloomed next spring and then prune it back, this will probably be about June. If just a few are way too long, you can selectively trim off the longest tips one or two at a time throughout the year. Here are some indoor growing tips you may find helpful.
Good luck with your gardenia, these are not at easy to grow.
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