Break, then pull on plant (10)
I believe the answer is:
snapdragon
'plant' is the definition.
(snapdragon is a kind of plant)
'break then pull on' is the wordplay.
'break' becomes 'snap' (snapping is a kind of breaking).
'then' is a charade indicator (letters next to each other).
'pull' becomes 'drag' (synonyms).
'snap'+'drag'+'on'='SNAPDRAGON'
(Other definitions for snapdragon that I've seen before include "One blooming" , "The blossom" , "that's in the garden?" , "Kind of antirrhinum" , "Perhaps Christmas entertainment" .)