Watermelon Mint Lemonade

 1-1/2 quarts water

1/2 cup sugar

2 sprigs mint, plus more for garnish

5-6 cups cubed watermelon

1/2 cup freshly squeezed lemon juice 

Bring water and sugar to a light boil until the sugar is dissolved and mixture is clear. Turn off the heat and add the sprigs of mint.  Allow mint syrup to cool and discard sprigs.  Add to a blender with the watermelon. Blend until smooth, then strain to remove seeds and pulp if desired.  Add lemon juice and stir.  Server over ice with mint garnish.