Plant used in chutneys or relishes (6)
I believe the answer is:
sorrel
'plant' is the definition.
(I know that sorrel is a type of plant)
'in chutneys or relishes' is the wordplay.
'in' indicates a hidden word.
'SORREL' is hidden in the letters of 'chutneys or relishes'.
'used' acts as a link.
(Other definitions for sorrel that I've seen before include "Light-chestnut horse" , "Sour-tasting leaves used in salads and sauces" , "bay" , "Light brown: salad leaf" , "Edible plant, horse of light reddish-brown coat" .)