In a pitcher, combine spritzer, coconut water, and sweetener. Stir until sweetener has dissolved. Taste and adjust sweetness as needed.
Place berries and sliced peaches into popsicle molds, I tried to choose larger berries that would stay where I placed them instead of sinking to the bottom.
Fill the popsicle molds with spritzer mixture, top with popsicle sticks, and freeze in the freezer for at least hours.
When you're ready to eat, run the mold under warm water, jiggling the sticks gently until they pull out of the mold.