The tiny yellow flowers of the Cornelian Cherry (Cornus Mas) will later form red cherry-like edible berries which are used in Eastern Europe for making jams, drinks etc and is regarded as having health benefits.  Probably those here will be eagerly devoured by birds. 
(Extra) We had a very pleasant wander around looking at the flowers and plants with Flumgummery and her husband and marvelled at the immense task facing those who were cutting the huge hedge. It was planted in 1906 with 200 little beech trees and is now 8m (26ft) high and 165m (180yd) long and takes about two weeks for two men to cut.  It must be very tiring holding a heavy hedge trimmer for hours so I hope that these workers share the task with others.