Mint care in winter
I have spearmints and peppermints growing in large pots in my patio. They flourished all through summer and fall. How do I care for them in winter? Can I leave them outside where they are subject to frost and snow and low temperatures? Should I bring them inside?
Outdoors is where they get the maximum sunlight.
You don't say what your hardiness zone is and I've looked at your profile and that doesn't tell me either. You say they are in large pots, but you also don't say what size. A 12" pot might be too small for hard freezes, but a whiskey barrel would probably be just fine. If you are in zone 8 or warmer, your mints should be ok in pots 14" or larger. Just make sure the soil doesn't dry out.
If you are in zone 7 to 5, you should be able to keep them just fine in a whiskey barrel. I'm in zone 7 and have overwintered mint in a whiskey barrel with no problems. There is enough soil to stay frozen and not completely thaw during warm ups.
Hope this helped,