First, you are going to make the mint simple syrup. In a small saucepan, add syrup ingredients. Bring to a simmer and stir until sugar is dissolved. Take off the heat and steep for 20 minutes. Remove the mint leaves and discard. Allow syrup to cool.
While the syrup cools, blend the strawberries and ¼ cup sugar in a blender. Strain into a large bowl with a fine mesh sieve to remove any seeds. If you like pulp, this step is optional.
In a large pitcher, add blended berries, lemon juice, mint syrup, and water. Stir to combine.