Paul is confused about a border flower (7)
I believe the answer is:
primula
'flower' is the definition.
(I've seen this before)
'paul is confused about a border' is the wordplay.
'is confused' indicates anagramming the letters.
'about' means one lot of letters goes inside another.
'a border' becomes 'rim' (I've seen this before).
'paul' with letters rearranged gives 'pula'.
'pula' placed around 'rim' is 'PRIMULA'.
(Other definitions for primula that I've seen before include "Spring flower" , "Polyanthus" , "Cowslip relative" , "Primrose" , "Flowering plant" .)