Dig up a small clump of Corsican mint from an existing stand of this plant. Be sure to include as much of the root system as possible.
Fill 3- or 4-inch pots about 3/4 full with any standard potting soil.
Set one 1-inch-diameter chunk of the Corsican mint on top of the soil in your pot.
Fill each pot with additional potting oil, gently pressing it down around the base of the chunk you planted.
Water well until water drains out the pot's drainage hole. Keep the soil in your newly planted Corsican mint moist and keep the pot in a partly shade area until the plant begins to spread. Transplant your division to the garden when this plant begins to fill the pot.