Like most Colubrids they breed when the female quits running and allows the male to copulate. Mine have bred on the ground and in the branches. When breeding/courting the action is obvious...much like big King Snakes..you might try separating them for a month at a time then do reintroductions...this is what I do and it allows me to gauge the female's receptiveness. As I mentioned before, if she's receptive the male should begin chasing her almost immediately.

Bill