Fellow erred — wrong ingredient for home-made wine (11)
I believe the answer is:
elderflower
'ingredient for home-made wine' is the definition.
(as in elderflower wine)
'fellow erred wrong' is the wordplay.
'wrong' indicates anagramming the letters.
'fellow'+'erred'='fellowerred'
'fellowerred' anagrammed gives 'ELDERFLOWER'.
(Other definitions for elderflower that I've seen before include "Blossom used in wine, cordial" , "Blossom used in wines and cordials" , "winemaker, maybe" , "Source of cordial and home-made wine" , "winemaker perhaps" .)