Jan my Tropical and Subtropical gardening book reads:
difficult under humid conditions, at its best in cooler regions.
You can propagate by seeds, by laying, or semi hardwood
cuttings taken in late summer or autumn.

Plenty of info in the link below, it wont let me link you to
Gordonia but click on 2001, then In the garden its under
Trees and Palms,hope it helps.

MM.

Here is a link that might be useful: Gordonia

Thanks Mistymorn
I'll look it up and see how I go
Jan

They grow fine here.
My mother has a nice one which flowers well every year. I have two. One is tiny and hasn't performed. The other is good - is about two years old - flowered last year.
I've seen them hedged and thriving at Mt. Tambourine which is cooler.
Perhaps your soil is the problem - have you tested it's ph?