I have two Italian plums, one planted 10 years ago and one planted 3 years ago. Both flower well, mostly in April and after the petals fall off there appear to be tiny green plums starting to grow. However by the beginning of June all of these have fallen off. We have had Mason bees every year. I also have another plum tree with 4 types of plum, 3 of which bloom at about the same time. One, a Beauty plum, flowers earlier and sets lots of fruit. An arborist has looked at the Italian plums and saw no sign of disease. The last 2 years other friends on Vashon Island have also had their Italian plums fail to set fruit, so our rainy Aprils may be part of the problem. However, a plum tree at a house we own in Seattle sets fruit every years. Is this a climate change problem, a pollination problem or something else? Do you have any suggestions? The Beauty plums lack flavor and are not very useful.