my gardenia is yellow
Gardenia branches are with few leaves. In addition to that most are yellow. Some buds are not flowering but become brown and fall down.
Certified GKH Gardening Expert
Yellow leaves normally signal that the plant is under some type of stress. In order to remedy the problem, you must first try to pinpoint the issue. This article should help you with that: https://www.gardeningknowhow.com/ornamental/flowers/gardenia/helping-a-gardenia-bush-with-yellow-leaves.htm
It is possible that you have thrips. They are hard to see and they cause damage to the buds like that. This article will help: https://www.gardeningknowhow.com/plant-problems/pests/insects/controlling-thrips.htm