I typed in the box "blue purple berry" and magically google images gave me some matches that quickly helped me to identify the Porcelain Berry I saw last week at NYBG. Visually this berry is stunning- the color ranges from turquoise blue through to bright purples. They looked strange and I assumed they were poisonous but apparently not. They are edible if not flavorful. So is the other fruit that I saw plenty of on trees and in wasted piles on the ground and paths. Its the fruit of the Kousa Dogwood which can apparently be made into a jam.