Grey hair will come up with age and no one can control it. But yes you can stop premature hair greying.
curry leaves handful;
Buttermilk 1/4th cup.
Crush the curry leaves finely and add to the buttermilk to form a smooth paste.
Apply as a hair pack on scalp ensuring that the hair strands are covered from root to tip.
After 30 minutes, wash off with a mild herbal shampoo.