Writing about border in bloom (8)
I believe the answer is:
primrose
'bloom' is the definition.
'writing about border' is the wordplay.
'writing' becomes 'prose' (I've seen this in other clues).
'about' indicates putting letters inside.
'border' becomes 'rim' (I've seen this before).
'prose' going around 'rim' is 'PRIMROSE'.
'in' acts as a link.
(Other definitions for primrose that I've seen before include "Woodland plant with pale yellow flowers" , "Pale yellow flower" , "Early spring flower" , "Yellow spring flower from promiser" , "Pale yellow- a primula" .)