Where did you purchase from? Too many peonies are being renamed by suppliers. Before buying if possible type the name in the search feature of you computer and press enter to see what comes up. Most will take you either to a nursery or the site I have linked you to. Scroll down to the name, click on for information. Gardenweb does not like the link this evening so you must copy and paste.

http://www.paeo.de/navigation/name_im.html

After I bought the first one that I purchased from Lowes I looked up 'Immaculate' like on the label. The only peony popping up was 'Immaculee'. The blossom did look like the one picture of that flower that I could find. The second I purchased at the grocery store, Giant. On the label it was just listed as 'White Double'. When I got it home, one the bottom of the 2 gallon pot was a sticker with the name 'Immaculate' as well. There wasn't a nursery name on the container or tag.

Thanks for the link. I'll go and take a look at it now.