Ok, I have this issue with my multi grafted plum tree and it is bothering me so much that I finally decided to join this forum to get answers. This is my first posting and don't even know if I am in the right place but here it goes. I have a multi grafted plum tree in which I had for the last 4-5 years. Every year the bottom 2 branches would blossom and give fruit but the rest of the tree does not blossom or fruit. Can someone figure this out for me? I prune the trees and fertilize every year yet it is only thos two branches that blossom and fruit. Please help.

I vaguely recalled seeing a few varieties said to be in the Damson family. When I did a search, I was surprised to find how many there are (Farleigh Damson, Prune Damson, Shropshire Prune, etc). This unusually detailed Wikipedia entry listed a dozen varieties, including two "white" Damson, which have green/yellow skin. This Ohio State article actually breaks plums into Damson, Asian, and European groups.

I think that two recent NY introductions are also in the Damson family: Blues Jam and Jam Session. I've ordered Jam Session for this spring, as it is supposed to lack the astringency, but still have Damson's brown rot resistance.