Is Mint deer resistant?

Left alone by deer for the same reason it is useful in the kitchen. Grow it in a sunken pot, because in open ground it will take the bed within two seasons.

Do deer eat mint?

Rarely. Rutgers rates the genus Rarely Damaged, A, Iowa State puts it in its top tier, and NC State lists deer and rabbits among what spearmint resists. The oil that flavors the leaf is the reason, and it is strong enough that mint sits with lavender and catmint among the few plants a deer will not test even in a hungry spring.

Where it grows

Anywhere, which is the problem. NC State's range for spearmint is zones 4a to 9b, full sun or partial shade, 1 to 2 feet, flowering summer into fall, and it tolerates wet soil and foot traffic. The warning is on every extension page. NC State: "The plant spreads aggressively," "The square stems can root wherever they touch the ground and it also spreads by rhizomes," and "Best grown in a container as it spreads rampantly." The UC Master Gardeners of Sonoma County: mint "should never be planted in the ground since, once established, they're nearly impossible to eradicate."

Protecting mint

Nothing. The question with mint is protecting the garden from it: a pot, a pot sunk to its rim, or the soil barrier NC State suggests where it is in a border. The ASPCA lists mint as toxic to dogs, cats and horses; NC State rates the severity Low, essential oils, "vomiting and diarrhea with large ingestions." The callout below carries it.

If it is browsed

A browsed mint is a pruned mint and it does not notice; it regrows from the runners and flowers on the new growth. Whether a border of mint keeps deer off what grows behind it is a different claim, and the USDA trial of twenty repellents is the nearest evidence: scent hung near a plant did less than spray on it. Plant mint for the mint.