Borders Trim's health farms (4)
I believe the answer is:
hems
'borders' is the definition.
(I have seen 'Stitched borders ' mean 'hems' so perhaps 'borders' could also mean 'hems')
I can't explain the remainder of the clue.
Can you help me to learn more?
(Other definitions for hems that I've seen before include "Stitched borders" , "Fringes" , "Bottom edges turned under and sewn" , "Stitched garment edges for Shem" , "Stitched edges of cloth or garments" .)