Dried lavender flowers (Lavandula angustifolia). Lavender flowers are a popular source of fragrance. They can be dried and used to infuse a room, or placed under a pillow to aid restful sleep. The flowers can be processed to produce an oil that is used in aromatherapy and in perfume. Lavender is also used as an antiseptic when applied to a wound, and as a tonic when taken as an infusion.