Boil 6 cups of water in a large saucepan. Turn off heat and add the mint. Cover and let steep for at least 30 minutes. Remove mint.
Place 1 cup of the tea in a blender along with the blueberries. Puree and then strain the mixture back into the rest of the tea through a fine mesh strainer. Stir in the honey until dissolved. Add the fresh lemon juice. Serve over ice cubes with a slice of lemon. (Or you could go a step further and freeze a small slice of lemon in your ice cube trays along with the water and then serve the tea over a lemon-flavored ice cube. Yum!) Enjoy!