Slightly bruised or wrinkled stone fruit is ideal for making the infused syrup; peaches and nectarines work too.
- 3 large sprigs lemon verbena or mint, plus more for serving
- 4 large red plums, cut into thin wedges
- 2 tablespoons fresh lemon juice
Combine tea bags, 3 lemon verbena sprigs, and 8 cups cold water in a large pitcher. Cover and chill at least 8 hours and up to 12 hours.
Meanwhile, bring sugar and 1 cup water to a boil in a medium saucepan. Add plums and reduce heat; simmer 10 minutes. Remove from heat and let steep 30 minutes. Strain plum syrup into a small bowl; stir in lemon juice. Cover and chill until cold, at least 30 minutes.
Remove tea bags and lemon verbena sprigs from tea and stir in ¾ cup plum syrup and 4 cups ice. Serve in ice-filled glasses garnished with more lemon verbena.
Do Ahead: Plum syrup can be made 1 day ahead. Keep chilled.