I would say they would crow at about three or four months of age. Were we live we can't have a rooster, not really allowed chickens either. It's been 11 yrs now having them. We had gotten two Cochin buff chicks, not sexed, it was a risk in case we had a rooster, well we did have one in the mix. We kept him hoping he wouldn't crow.
and he never did. it was such a great experience having him. We hatched chicks and watched him with the ladies. He was so passive and beautiful. He is the one in the picture in my name. We had him for four wonderful years. He was luck, not sure if that happens very often. You might get lucky and he might not crow.
. Keep him until he does.

