Step 1

Put sugar and 1 cup water into a medium saucepan over medium heat. Bring to a simmer, stirring until the sugar has dissolved. Remove from heat; add herbs. Cover; let cool completely.

Step 2

Pour syrup through a fine sieve into a small bowl; discard herbs. Stir in lemon juice. Refrigerate at least 30 minutes.

Step 3

Fill glasses with ice. Add 2 to 4 tablespoons syrup; top with sparkling water or club soda, and stir.