Risk redeveloping garden (6)
I believe the answer is:
danger
'risk' is the definition.
(synonyms)
'redeveloping garden' is the wordplay.
'redeveloping' indicates an anagram (I've seen 'redeveloped' mean this).
'garden' with letters rearranged gives 'DANGER'.
(Other definitions for danger that I've seen before include "Peril, hazard" , "Ranged about in some peril" , "Red flag, for example" , "Garden (anag) - peril" , "Undesirable possibility" .)