Plum diseases

scooby

Hi,

I have a victoria plum tree at my allotment.  I had 4 plums the first season and they were lovely. The next year I had a few more but some turned deformed and shrivelled.  This year I had a lot of blossom and lots of plums formed but they all turned deformed and shrivelled.  I've had a look at various pest and disease websites but cant see anything that quite fits my problem.  Tree itself looks healthy.