Shoots, flowers, evergreen, peace at last (5,4)

I believe the answer is:

opens fire

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'shoots' is the definition.
(opening fire is a kind of shooting)

'flowers evergreen peace at last' is the wordplay.
'flowers' becomes 'opens' (I am not sure about this - if you are sure you should believe this answer much more).
'evergreen' becomes 'fir' (I've seen this before).
'at last' indicates one should take the final letters.
The final letter of 'peace' is 'e'.
'opens'+'fir'+'e'='OPENS FIRE'

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I've seen this clue in The Independent.

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