Hi plumism - this forum is a great place for learning all about new varieties and care for hydrangeas.

I also visit this forum -

http://www.helpfulgardener.com/phpBB2/viewforum.php?f=3

and for ordering Hydrangeas these -

http://hydrangeasplus.com/

http://www.hydrangea.com/

and just to read about them and learn alot more I visit the link attached.

Hope this helps!

Here is a link that might be useful: Hydrangea Help

I highly recommend checking out:

Hydrangea Farm Nursery on Nantucket
www.hydrangeafarm.com

Friends of the Shamrock Hydrangea Collection http://www.hortensias-hydrangea.com/

Wayside Garden Center
www.waysidegardencenter.com

Forever and Ever series of hydrangeas
http://www.foreverandeverplants.com/Index.aspx/GardenFavorites/Hydrangeas

Endless Summer hydrangeas
www.endlesssummerblooms.com

and if you are interested in new introductions:
http://www.plantintroductions.com/

and also you can check out some hydrangea breeding research:
http://ddr.nal.usda.gov/handle/10113/37816

The book Encyclopedia of Hydrangeas is a gold-mine of information and photographs. Nothing else comes close, even if it is about 10 years old. I hope this helps! Hydrangea literature and websites are addicting so consider yourself warned.

I'm trying to find out what zone southeastern PA is in
so I know what kind of sunlight etc. to plant a hydrangea.