Using a slice of lemon, wet half the rim of a Collins glass. Roll the rim in white sugar. Fill the glass with ice cubes to let chill. Place the juices, syrup and gin into an ice-filled cocktail shaker. Shake for 10 seconds. Strain into the Collins glass over ice, and top with soda. Give a quick stir to mix. Garnish with a lemon wheel on the rim, and blueberries on top in the glass.