Answer: Gardenias are such awesome plants that I'm glad you have several in your landscape. Rather than try to answer all your questions in the short space I have to respond, I'll direct you to the following website, sponsored by the University of Florida. The page deals directly with gardenias, their needs and how to troubleshoot problems.
After you've read the publication you'll have a better understanding of gardenias, and an even deeper appreciation for them.
Best wishes with your gardenias!
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