Make an ice bath by filling a large bowl halfway with ice cubes and water. Set aside. Heat the water in a small saucepan over high heat to boiling. Add sugar and stir to dissolve. Add lemon verbena. Remove from the heat and let steep until tepid, about 15 minutes.

Remove the lemon verbena and discard. Place the berries in the jar of a blender. Pour over the simple syrup and add the salt. Puree until smooth.

Cool completely over an ice bath or refrigerate until cool. Churn the sorbet according to the machine instructions.