Q.Many buds on my recently revived gardenia plant. Some flowered, many remain unopened and the same size…no change
It is planted in a topsoil mix (my mistake) and was overwatered and left to stand in water. It’s in same soil mixture, same pot but watered less and drained perfectly. It grew all new leaves and produced buds on almost every branch, four of which bloomed and are ready to drop. The rest of the buds remained “stuck” having no change or blooms. I water infrequently and have used a Miracle Grow acid food. It’s getting to be freeze time here and I need to bring it indoors. Will that stop the blooming process or is it already too late for these buds to open?

Certified GKH Gardening Expert
Maintaining a regular level of moisture in your soil is important. Your plant has experienced water stress and should behave differently once it gets accustomed to a constant, unvaried watering schedule.
Since they are tropical plants, Gardenias thrive when the nighttime temperature only drops to around 60°F and they like 70–75°F during the day. This article has additional info for you:
https://www.gardeningknowhow.com/ornamental/flowers/gardenia/gardenia-flowers-gardenia-buds-falling-off-plant.htm