Hello my cherries are dropping
Cherries can drop their fruits for several reasons. Poor pollination - bee activity can be low during cool wet weather. Lack of a pollinizer tree - Sweet cherries require a pollinizer tree for cross pollination. Stress, poor soil conditions, and a frost during bloom can affect the fruit. Check for insect and disease on the fruits. Open up the fruit and look inside for insects.
See our publication on stone fruits for more information http://extension.umd.edu/sites/default/files/_images/programs/hgic/Publications/HG77_IPM_Series_Ston...