Plant with leaves when it's cold (5)
I believe the answer is:
inter
'plant' is the definition.
(to inter in the ground)
'with leaves when it's cold' is the wordplay.
'with' becomes 'w' (short for with).
'leaves' suggests deleting specific letters.
'when it's cold' becomes 'winter' (the weather is cold in winter).
'winter' with 'w' removed is 'INTER'.
(Other definitions for inter that I've seen before include "Place in ground" , "Nitre (anag.)" , "promoting cessation" , "foreign team" , "Place into grave, tomb" .)