I came across an amusing 5-year-long thread titled "So you want to grow a gardenia, huh? (also known as the infamous suicidal gardenia thread)". From the parts I read, it sounds like gardenias yearn to be ignored and left to their own devices, and that they grow best that way. Although it seems to help if you have them planted in the ground in the South, as opposed to in a pot in California.
Although there's also this post (edited for readability):
"... After 3000 hrs on the internet, gardening books and help from 300 professional growers and 4 gardening CDs, here is what I have learned. They like water but you have to keep them semi-dry. They love sun but you have to keep them in the shade. You feed them often. Described as somewhere between two days and two years only on Sundays with a blue moon rising. They love northern exposure if you have them on the southern. They love acid and iron unless you give it to them. They love to grow spider mites, which you can't see, and aphids. I have found that if you buy older plants, they take longer to die. ..."
Of course, that whole thread had absolutely nothing to do with the info I was originally searching on.
Although there's also this post (edited for readability):
"... After 3000 hrs on the internet, gardening books and help from 300 professional growers and 4 gardening CDs, here is what I have learned. They like water but you have to keep them semi-dry. They love sun but you have to keep them in the shade. You feed them often. Described as somewhere between two days and two years only on Sundays with a blue moon rising. They love northern exposure if you have them on the southern. They love acid and iron unless you give it to them. They love to grow spider mites, which you can't see, and aphids. I have found that if you buy older plants, they take longer to die. ..."
Of course, that whole thread had absolutely nothing to do with the info I was originally searching on.