Clue: Tough grass nurses simmering hatred, ready to baste again? (10)
Answer: RETHREADED
Explanation: Definition: ready to baste again
**REED** ("tough grass") *nurses* ***(hatred)** 
*I hadn't come across "baste" meaning "to sew with long, loose stitches, as in temporarily tacking together pieces of a garment while it is being made" before, but at least one online dictionary has this as definition 1.