Many herbs produce flowers from the plants that also grow the herbs. They are many different colored flowers though. Several of the herb plants produce purple flowers. A certain type of anise produces purple flowers. It is called the Anise Hyssop. This herb produces long rigid purple flowers that stand straight up. These plants grow back every year. Lavender is a common herb, but it is also a common flower.
It is known for having a dark purple color. They grow from tall thin stalks. The purple coneflower is obviously purple based on its name. It has many petals that surround the ball-like brown center. Basil can be extracted from the Thai Basil plant, but it also produces purple flowers. They bloom around August or September.