Answer: The control really depends upon the insect so without knowing what you're dealing with, I can't offer any chemical suggestions. You can try rinsing the plant off with a strong stream of water to remove the pests, or you can try collecting a few and taking them to your local nursery for identification. Once you know what you're dealing with, the nursery can recommend a chemical control. (Not all chemicals are effective against all pests and not all are safe to use on your gardenia - your nursery staff will be able to help you find just the right product.)
Best wishes with your gardenia!
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