And it will be fairly evident when he does. A place with low turnover would be one where the manager can confidently look you in the eye and declare he has low turnover.
It is rare for hiring managers to be effective bald-faced liars (HR on the other hand suffers from no such weakness), so they will try to dodge the question instead. Dodgy hiring managers is pretty much the signal for "run for the hills".
It would be interesting if you could measure this with LinkedIn - as in looking at the profiles of all developers who worked for company X and determine how long they stayed on average. Of course it would rely on people actively updating their profiles. But if you could it would be interesting to see how much high turnover at a company correlated with bad reviews for said company on sites like Glassdoor.
But how do you find out if turnover is high? Just ask, I suppose, but a manager is going to try to downplay it, since he's selling the company to you. Hit or miss whether workers will be truthful about it, between wanting to be team players and not telling tales out of school.
I'm leaving a place with high turnover now. I had no idea. Although I could have entertained some suspicion when my agency told me how much they love this place; churn is lucrative for some people.