Rinse off the mint leaves, and place them into a large saucepan. Crush with a potato masher or the bottom of a jar or glass. Add water, and bring the mint to a boil. Remove from heat, cover, and let stand for 10 minutes. Strain, and measure out 1 2/3 cups of the mint.
Place 1 2/3 cups mint into a saucepan. Stir in the lemon juice and food coloring. Mix in the sugar, and place the pan over high heat. Bring to a boil, stirring constantly. Once the mixture is boiling, stir in the pectin. Boil the mixture for a full minute while stirring constantly. Remove from heat, and skim foam off the top using a large metal spoon. Transfer the mixture to hot sterile jars, and seal.
Place a rack in the bottom of a large stockpot and fill halfway with water. Bring to a boil over high heat, then carefully lower the jars into the pot using a holder. Leave a 2 inch space between the jars. Pour in more boiling water if necessary until the water level is at least 1 inch above the tops of the jars. Bring the water to a full boil, cover the pot, and process for 10 minutes.