Mix juice and syrup in mixing bowl for 12 seconds / speed 3. Rub the zest of the lemon with a kitchen grater. Pour juice and syrup over lemon zest, herbs and cucumber slices. Cover and leave to stand in the refrigerator for about 2 hours. Then pour through a fine sieve.
Put the remaining herbs, eight cucumber slices and ice cubes in a bottle. Pour the juice mix and mineral water on top.