Leave to set climbing rose (3,2)

I believe the answer is:

got up

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'rose' is the definition.
('get up' can be a synonym of 'rise')

'leave to set climbing' is the wordplay.
'leave' is a reversal indicator (I've seen 'left' mean this).
'to set' becomes 'tog' (I can't justify this - if you can you should believe this answer much more).
'climbing' becomes 'up'.
'tog' back-to-front is 'got'.
'got'+'up'='GOT UP'

Can you help me to learn more?

(Other definitions for got up that I've seen before include "20 [ROSE]" , "Ascended" , "Arose" , "made to look good?" .)

I've seen this clue in The Telegraph.

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