Make simple syrup. Combine 1/2 cup water and 1/2 cup sugar in a small saucepan. Bring to a boil over medium heat, stirring until sugar dissolves. Add 1 packed cup lemon verbena leaves, remove from heat, cover and let steep until cool. Strain.
Blend and freeze. Combine 1 pound blueberries, syrup, and juice of 1 lemon in a blender. Blend until smooth. Pour into popsicle molds and freeze until solid, at least 4 hours.
Unmold and enjoy. Dip the bottom of the mold in hot water until the popsicles release from the mold. Gently pull out and enjoy!