too windy, flowers fall off too soon
tree still young, sometimes up to 5 years before first fruit
some kind of pest/disease/moth
too cold at night
lack of flying insects, no pollination
what you can do
proper fertelizing
pruning (be careful not to leave open "wounds")
testing - cover a few flower clusters with paper bags and see if fruit develops
treating disease especially moth
and if all else fails....praying?
HAGWE
Asi