Son folded sheets for landowner (6)
I believe the answer is:
squire
'landowner' is the definition.
(I have seen 'Old landowner' mean 'squire' so perhaps 'landowner' could also mean 'squire')
'son folded sheets' is the wordplay.
'son' becomes 's'.
'folded sheets' becomes 'quire'.
's'+'quire'='SQUIRE'
'for' is the link.
(Other definitions for squire that I've seen before include "[PILGRIM in the CANTERBURY TALES]" , "Old landowner" , "Local landowner; knight's attendant" , "English country landowner" , "Country gentleman" .)