I found myself in the Philly area a couple of weeks ago and was able to visit the Heronswood Hellebore Open in April. It was very well run and the weather was great. Good selection of Hellebores and other perennials. This was a local article that was written later - sums it up pretty well.
http://www.mcall.com/features/custom/hg/garden/nurseries/all-gardenstopshops0427.5817119apr27,0,2361228.story
If you find yourself in the Philly area - here are the next few Opens
http://www.heronswood.com/openevents.asp
Heronswood Opens
