Part of the garden we turn up to sprinkle (5)
I believe the answer is:
bedew
'sprinkle' is the definition.
(I've seen this in another clue)
'part of the garden we turn up' is the wordplay.
'part of the garden' becomes 'bed' (I can't justify this - if you can you should give a lot more credence to this answer).
'turn up' shows that the letters should be reversed in order.
'we' backwards is 'ew'.
'bed'+'ew'='BEDEW'
'to' acts as a link.
Can you help me to learn more?
(Other definitions for bedew that I've seen before include "Sprinkle with water (poetic)" , "Moisten (poetic)" .)