Three closely related trees have white flowers in spring – Cherry Plum, Blackthorn and Wild Cherry. They are all members of the Prunus genus in the Rose Family and have very similar flowers. The Prunus genus of over 400 species of trees and shrubs includes Wild Cherry, Flowering Cherries, Plum, Apricot, Peach, Almond, Blackthorn and Bird Cherry. These three species have flowering periods that may overlap and they can easily be confused. Each flower has 5 green sepals, 5 white petals, many yellow anthers and 1 green style. The sepals lie under the petals and have evolved to protect the bud before flowering. Their shape after flowering is the key to correct identification. One other difference is that Cherry Plum and Blackthorn flowers are ‘solitary’ (one bud produces 1 flower) but Wild Cherry flowers are in the form of an ‘umbel’ where one bud produces a number of flowers.
The sepals of the Cherry Plum are ‘reflexed’ i.e. bent backwards.
The sepals of the Blackthorn are not reflexed i.e. not bent backwards.
The sepals of the Wild Cherry are ‘reflexed’ i.e. bent backwards like the Cherry Plum.