What I am trying to do, just for fun, is to put some decent fruit onto the ornamental plums planted along my street. We have nice flowering, sidewalk littering, plums throughout our neighborhood, and many of us have plums in our backyards, so I thought that I would enhance the trees with decent fruit. I have had poor results grafting the European plum scions onto Japanese ornamental trees.

The scions readily available are types of purple Italian plums, also available are lots of peach and some nectarines.

The rootstock are likely 30 yrs old so I have attempted cleft grafting onto upright, branch watersprouts. I trimmed several of these trees 2 years ago and they have happily thrown up lots of growth, but mainly upright spurs. I attempted to cleft graft onto these 1/2 " spurs with my scions, taped and waxed however everyone croaked.

So my question actually is, will the Japanse rootstock take a European plum scion?