Hi

I have a four year old orange tree which last year I couldnt get to bloom,but this year it was covered in sweet scented blossom which turned into small oranges but then having grown into the size of half your small finger nail they all but two dropped off.Its a navel tree which still looks very healthy with dark green leaves and very rigorous growth.Its in a very large frost free earthen ware pot and carefully fed and watered.Can anyone tell me the cause?Any help will be gratefully appreciated.

Peter.