Hedging shrub (6)
I believe the answer is:
privet
'hedging shrub' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for privet that I've seen before include "Garden hedge plant" , "Half evergreen European shrub of the olive family" , "Hedge for pert Vi" , "Common hedge shrub" , "Bushy evergreen shrub used for hedges" .)