Add half the water and grapes in a blender. Pulse until fully blended. Add more water if necessary.
Strain the grape juice to filter out the grape skins.
Pour into pitcher and taste. If needed add additional water and stir well.
Add the lemonade to the grape juice and stir well.
Taste and add additional lemonade or water to taste.
If you like your drinks sweet you can make a simple syrup and add it to the juice. (Heat 1 cup of water and add 1 cup of Monk Fruit, remove from heat. Stir until sugar dissolves and chill before adding to the juice.)
Serve over ice with fresh mint leaves and frozen sliced grapes for garnish.