We have a 4 year old Victoria Plum tree. We prune it, and water it well. We were excited this year when it had the best show of blossoms so far. After blooming, a large number of tiny green plums began to form. Sadly, one by one they dropped off, leaving us with six small red deformed plums, and one normal green plum.
How can we help this tree produce a full crop of healthy fruit?