They make great hedges.
Gardenias are usually reported to be difficult to grow. The leaves turn yellow and gardeners panic. Give them some water. Pick off the yellow leaves, they are old. New ones take their place. Gardenias like good soil, excellent drainage and bright light. A spritz of oil soap for white fly and sooty mold and they're good.
Last year I gave a good pruning to these six along the driveway that I enjoy on my hike to the mailbox. They are bigger than ever and just starting to bloom.
MIL called them Cape Jasmine. One of my favorite broadleaf evergreens, Gardenias.