Blue River II Improved white hibiscus moschuetos
I have a plant that is a must for a moon garden, although it is not scented. It is the Blue River II Improved hibiscus moscheutos and the flowers are huge and solid white. The first time it bloomed, I gasped. It was as if the moon had come down to earth as a flower......really......that dramatic. The flowers are dinnerplate size and really stand out at night. I think they are pretty hard to locate. I bought mine at a botanical garden plant sale. The website below has a picture, but does not indicate the enormous size of the flower. It grows in zones 5 - 9.
Here is a link that might be useful: Missouri Botanical garden