They can be wrapped, mulched, placed in an unheated garage, etc. A worthy experiment would be to plant your mint in good a good potting mix (which is much more appropriate for containers than dirt) and then sink the entire container into the soil to over winter.

How do I prepare my mint for winter?

If you do want to preserve mint for cooking over the winter months, it's better to harvest clean, fresh leaves now, chop finely, pack into ice-cube containers, immerse thoroughly in water and freeze.

What do you do with mint plants in the winter?

If you do want to preserve mint for cooking over the winter months, it's better to harvest clean, fresh leaves now, chop finely, pack into ice-cube containers, immerse thoroughly in water and freeze.