Tree adds lacy fringe as it gets older (7)
I believe the answer is:
elderly
'older' is the definition.
(synonyms)
'tree adds lacy fringe as it' is the wordplay.
I cannot really see how this works, but
'tree' could be 'elder' (elder is a kind of tree) and 'elder' is located in the answer.
This may be the basis of the clue (or it may be nonsense).
'gets' is the link.
Can you help me to learn more?
(Other definitions for elderly that I've seen before include "Past middle age, a senior citizen" , "Aged" , "Long in the tooth" , "Silver" , "over the hill" .)