Basically, what Robert said.

I'll add that I don't know why anybody in these parts would grow any
other cultivar than Chuck Hayes. It was developed in Virginia Beach, so
we live in the target climate for it, and it has two blooming
periods...I think I posted somewhere that I was able to take my Mom
some gardenia blossoms last Thanksgiving!


In article k.net,
Robert wrote:

Gardenias can live in sun to partial shade and like acidic soil. I have a
bunch of Chuck Hayes Gardenias planted as foundation plantings along the
front of our house and they have done well there. We are surrounded by tall
pines so they only get partial shade.

Our soil here is pure clay so when I planted our Gardenias I had to heavily
amend the soil with compost, topsoil and peat moss to about 18" to get
anything that they would grow in. Once I did that they transplanted and grew
just fine. They were actually the first successful shrubs that I've ever
planted.

We fertilize with Holly-tone in the spring and other than that and an
occasional pruning they've been pretty easy. Last fall we had an aphid
infestation which is what caused a lot of the problems I've seen this spring
but they should perk up soon.

The only Gardenias I know of that can survive the winters here are Kleim's
hardy and Chuck Hayes. There are some posts on Gardenweb from people who
have had success with Veitchii making it through some cold winters.

We got our Gardenias from Red Mill Nursery in Durham and have been really
happy with them and all of the plants we've bought there.

Robert