This is ground where plant reported (5)
I believe the answer is:
flour
'this is ground where plant reported' is the definition.
The definition suggests a singular noun which matches the answer.
This is the entire clue.
Can you help me to learn more?
(Other definitions for flour that I've seen before include "Cake ingredient" , "Delivery from miller" , "Dusty white stuff" , "Wheat meal" , "Fine-ground grain" .)