Said to put in a grass border (7)
I believe the answer is:
reputed
'said' is the definition.
(thesaurus)
'put in a grass border' is the wordplay.
'in' is an insertion indicator.
'a grass border' becomes 'reed' (I can't explain this - if you can you should give a lot more credence to this answer).
'put' inserted into 'reed' is 'REPUTED'.
'to' is the link.
Can you help me to learn more?
(Other definitions for reputed that I've seen before include "Alleged" , "Erupted (anag)" , "Generally believed to exist" , "Rumoured, reckoned" , "Supposed" .)