Refuse to commit oneself about the garden perhaps (5)
I believe the answer is:
hedge
'garden perhaps' is the definition.
The definition and answer can be both man-made objects as well as being singular nouns.
Maybe there's an association between them I don't understand?
I don't understand how the rest of the clue works.
Can you help me to learn more?
(Other definitions for hedge that I've seen before include "Fence of bushes or small trees" , "Growing division" , "cover?" , "Barrier of shrubs or bushes" , "Qualify by conditions; boundary of bushes" .)