01 - In a small saucepan, combine sugar and 1/2 cup water. Heat over medium heat, stirring continuously, until the sugar fully dissolves. Set aside to cool.
02 - Add sliced peaches, freshly squeezed lemon juice, and lemon zest to a blender. Purée on high until completely smooth.
03 - Pour the peach purée through a fine-mesh sieve into a large pitcher, pressing with a spatula to extract liquid. Discard the retained pulp.
04 - Add the cooled simple syrup and 3 cups of cold water to the pitcher. Stir thoroughly until well blended.
05 - Taste the lemonade and adjust sweetness or tartness by adding more sugar or lemon juice as desired.
06 - Refrigerate for at least 1 hour before serving, or pour immediately over ice. Garnish each glass with fresh mint, peach slices, and lemon wheels.