shrivelled plums?

can anyone tell me why some plums have shrivelled away to almost nothing while on the tree but others on the same tree are big and plump? is it some kind of infection or it it weather produced?

 

We have the same problem each year on our plum trees,so you are not alone.We have always been mystified as to why it happens.Perhaps there isn't enough moisture going to all the fruits especially if it is a heavy crop.
Sorry I cannot be of anymore help.

Kandy

 

My client and I have been ogling her Greengage for weeks. It is seriously laden with delicious ripening fruit. This weekend the rain just tipped down. My client came out this morning, almost inconsolable; absolutely all the greengages have swollen up and split! Apparent;y they are now ripe so its time to eat them before the wasps get there.

Sorry L-G, know its no help to you, but needed to tell my story