vazime:

Sure there is some reason why. The problem is to figure out what that reason or reasons are, but you are not giving us much information to work with. How old is the tree? Has it given you peaches before? How big were the peaches when they dropped? Did you thin them at all after fruit set? Have you looked at the little peaches closely to see if they were damaged by insects before they fell?

If you can provide a little more background information, somebody might be able to help you. Don't be shy about writing a little more. Nobody will get bored.

Don Yellman, Great Falls, VA