EE-Ev
very early flowering time (May)

E
early flowering time (June 1-15)

EM
early middle (June 15 to July 15)

M
mid-flowering period (July 15 - August 1)

ML, MLa
the second half of the flowering period (August 1 - August 15)

L,La
late flowering period (August 15 - August 30)

VL
very late (September)