Annoying press broadcast on moorland plant (8)
I believe the answer is:
needling
'annoying' is the definition.
(I've seen this before)
'press broadcast on moorland plant' is the wordplay.
'press' becomes 'knead' (kneading bread is pressing it).
'broadcast' indicates a 'sounds like' (homophone) clue (how the word might sound on the radio or TV).
'on' says to put letters next to each other.
'moorland plant' becomes 'ling' (ling is a type of heather).
'knead' is a homophone of 'need'.
'need'+'ling'='NEEDLING'
(Other definitions for needling that I've seen before include "Aggravating" , "Provoking or annoying by continual criticism" , "irksome" , "Goading or provoking" , "Doing embroidery" .)