Susan Feniger's refreshing green tea–based mocktails would also be great spiked with gin. While the ingredients can be prepped in advance, it's best to blend everything together just before serving for the most vividly green drinks.
In a bowl, toss the cucumbers with the mint leaves. Transfer half of the mixture to a blender and puree until chunky.
In a large pitcher, combine the lemon juice, agave and matcha powder with 5 cups of ice water. With the blender on, add half of the lemon mixture to the puree and blend until very smooth. Transfer to a punch bowl. Blend the remaining cucumbers, mint and lemon mixture until very smooth and transfer to the punch bowl. Season the drink lightly with salt and serve in ice-filled glasses.