Garlic does tend to repel ahpids on roses and fruit trees. I also like to plant garlic around saplings because I feel like it helps the roots.

Hi Bonnie~
If you want the same kind of look as the society garlic, you could try Silvery Sunproof Lilyturf.Bold yellow and white striped dark green foliage with flower spikes of soft lilac highlight this evergreen perennial in summer. A perfect choice for ground cover, edging a walk or a filler in a tub planting. Takes full sun in cool climates. Partial sun. Clumping, blade-like foliage 15 to 18 inches tall, flowers above foliage. Might look good but they aren't fragrant

A cold zone 7 winter will probably take out your Society Garlic, which is much less pungent in cool summer areas like the San Francisco Bay Area, where it tends to bloom all year round and the foliage scent is only noticeable on very hot days or if it is bruised. It might better survive your winters if it were mulched in winter, and it is unlikely to remain evergreen much below 27F, particularly if it happens repeatedly.

I agree that the liriope (Lilyturf) would look very nice with your gardenia. If you aren't looking for year-round foliage then grape hyacinths are also very very cute and smell heavenly in the early spring. They are so dependable too! (Can you tell I'm biased, I have them growing around my gardenia at the front door). You could also interplant the grape hyacinths with the lilyturf...

I don't think Society Garlic repels anything, it's not a garlic but a plant of the amaryllis family.