First year flowering bushy plant producing small, tubular flowers that are usually deep blue or violet. The leaves of hyssop are narrow, lance-shaped, and dark green. They are about 2.5 to 5 cm long and grow in opposite pairs along the stems. The leaves are aromatic, with a slightly bitter, minty flavor.

The leaves and flowers of hyssop are used as a flavoring in cooking. The flavor is strong, so it is often used sparingly. Hyssop has been traditionally used for its expectorant, antiseptic, and anti-inflammatory properties. It can be toxic in large doses.

The essential oil extracted from hyssop is used in aromatherapy and perfumery. It has a sweet, camphor-like aroma.