Turfed out when retaining information that's productive (7)

'productive' is the definition.
(fruited trees produce fruit)

'turfed out when retaining information' is the wordplay.
'out' indicates an anagram (out can mean wrong or inaccurate).
'when retaining' means one lot of letters goes inside another.
'information' becomes 'i' (common abbreviation for information).
'turfed' anagrammed gives 'fruted'.
'fruted' placed around 'i' is 'FRUITED'.

'that's' is the link.