Baffle gardener, initially, with passion flower (8)
I believe the answer is:
foxglove
'flower' is the definition.
(thesaurus)
'baffle gardener initially with passion' is the wordplay.
'baffle' becomes 'fox' ('fox' can be a synonym of 'baffle').
'initially' indicates taking the first letters.
'with passion' becomes 'love' (I can't justify this - if you can you should believe this answer much more).
The first letter of 'gardener' is 'g'.
'fox'+'g'+'love'='FOXGLOVE'
Can you help me to learn more?
(Other definitions for foxglove that I've seen before include "Common wild flower" , "Flowering plant that's source of digitalis" , "Source of 1 dn" , "Plant (of the genus 10 down) with bell-shaped flowers" , "Tall plant with purple or white flowers - vulpine?" .)