They shed when they grow, and the younger the frog the more shedding there is, I had mine shed every day to every other day as youngsters, I'd say they probably shed a couple times a month at least... hard to tell when you don't catch them at it, but loose bits and strings of skin are a tell tale sign. They can also shed a lot when they have a bacterial or fungal issue going on, and they try to get rid of the infection.