Lemon Verbena is a herb I must have in the herb garden each year. Just to touch it smells divine. Instead of adding a slice of lemon to your iced tea, add a small twig of lemon verbena. You can add a twig to lemonade or cocktails also. Lemon Verbena can also flavor pound cakes, custards, shortbreads, and creams, plus add a citrusy-sweet note to a vinaigrette.
Organic Gardening recommends using it as follows:
Cut 10 6-inch-long stems from your lemon verbena plant. Strip the leaves from the steams and crush them in your hands until they release their scent. Bring 1 cup of water to a boil in a saucepan. Add the leaves and 1 cup of sugar. Stir the mixture constantly until the sugar dissolves. Remove from heat, cover, and set aside for 24 hours. Then pour the syrup through a strainer to remove the leaves. Drizzle the syrup over fresh fruit or use it to sweeten iced tea.
Personally I wouldn't want all that sugar; so I might follow the instructions but just leave out most or all of the sugar, then use it to make iced tea or to add to other recipes for flavoring. I have made and served Lemon Verbena iced tea for parties in past summers.