This tea is called kumisukuchin tea in Japan, a name originating from the Malay word Kumis Kucing from the plant, Cat's Whiskers (the pistils of the flower resembles a cat's whiskers). The leaf and stem are made into tea that is thought to have various benefits.
The tea is contains a high amount of rosmarinic acid (wikipedia) and potassium.
Place one tea bag into teapot and pour hot water. Wait until the color turns to your taste and remove tea bag. Pour into cup to drink.