I'm guessing twice a day watering might be too much, and is encouraging fungus, etc...?

Have you looked up watering requirements for this plant?

In Florida pest and disease issues are also prevalent and could be involved. Maybe try taking samples of affected parts to your nearest USDA Cooperative Extension Service branch office.

I grow all of them in Sarasota, on the West coast. They are planted in the ground, pure sand, no additional anything. I rarely water as we have no sprinklers. They do very well. I don't even fertilize.

I would strongly suggest pulling up the wood chips. These plants do not like wet feet. I certainly wouldn't fertilize this time of year. Most of all, stop watering!

We just finished the rainy season and if you were watering with all the rain, that is too much.

Let them all dry out.

Jane

Agree with everyone above.

Gardenias also love Epsom salts. Don't ask me why, but they get magnesium deficiency quite easily. I was told by a horticulturist from the Sarasota extension service years ago that it happens when their roots hit the hardpan under our very meager layer of topsoil. It's rescued quite a few gardenias over the years. Magnesium deficiency shows up as yellowing leaves with dark green veins starting at the bottom of the plant, but can spread to the entire plant eventually.

The Problem is where they are planted is they get a shower from the HOA Sprinkler System, I have cut back on watering twice a day and only do it in the morning, Sorry for the Delay on responding , but I have been busy, will take away the Mulch in the Morning

and PS to Linda Leaf, If my Linda (Wiltsey, Sents_from_heaven) was still alive, she would have Copons and Rebates for you, as from 2014-2016 she was a Weekend Warrior at Home Depot and Lowes, and was a Bayer Rep.

Ted, I was thinking about Linda the other day when I was perusing some old threads.