Beginning to enjoy flower festival (6)
I believe the answer is:
easter
'festival' is the definition.
(I've seen this before)
'beginning to enjoy flower' is the wordplay.
'beginning to' indicates taking the first letters.
'flower' becomes 'aster' (aster is a kind of flower**).
The first letter of 'enjoy' is 'e'.
'e'+'aster'='EASTER'
(Other definitions for easter that I've seen before include "Annual religious festival" , "Christian festival in Spring" , "A terse sort of Spring festival?" , "Sort of tide" , "Resurrection festival" .)