I know it depends on food, care, environment and stuff but around how long does it take a box turtle to reach 4 inches long?
I believe average is 3-4 years for a CB and raised. Not only does care play a big part into it but some turtles do grow faster than others. I had one that in November (before going down for the winter), at 1 and a half years old, was pushing 3 1/2" while it's clutch mates were all under 3". I'm pretty certain that individual will reach 4" or more by the end of next summer. Note that this is only in reference to Ornates, I've not kept any of the non native box turtles.