Question
I have grown culinary herbs in my south and east facing windows for years here in NYC. I've had bad luck wintering over mint. Do you recommend bringing them indoors for the winter or leaving them outdoors? Thanks?

Answer
You can do either or both.  For any perennial herbs that survive the winter in your climate I would leave them outside.   If you would like to harvest them over the winter you could have additional plants inside.  I sometimes plant some basil or other herbs just for indoor, wintertime use. For perennials that will not survive in my climate (zone 6) I keep them in 10" or larger pots, move them outside for the summer and back in before the temperatures drop below 45 F.
Do you overwinter your mint outdoors in a pot or in the ground?  Does it receive water and snow cover over the winter?  I leave my mints (I have several varieties) outside in 16" pots all winter and they have survived for years that way.  They do get watered from snow and rain and usually there is snow cover.  Snow helps to insulate when temperatures are especially low.