English plant, say, given to German as a seasonal gift (6,3)
I believe the answer is:
easter egg
'a seasonal gift' is the definition.
(gift given at Easter)
'english plant say given to german' is the wordplay.
'english' becomes 'e' (abbreviation).
'plant' becomes 'aster' (aster is a kind of plant).
'say' becomes 'eg' (short for 'exempli gratia', 'for example' in Latin).
'given to' is a charade indicator (letters next to each other).
'german' becomes 'g' (abbreviation).
'e'+'aster'+'eg'+'g'='EASTER EGG'
'as' is the link.
(Other definitions for easter egg that I've seen before include "festive gift" , "seasonal treat" , "chocolate gift" , "DVD feature?" , "Candy to celebrate Spring festival" .)