There are 28 species of the aromatic, evergreen, shrubby perennials, all with small linear leaves and spikes of fragrant, usually purple or blue, two-lipped flowers. Uses: Aromatic oils glands cover all aerial parts of the plants but are most concentrated in the flowers. The flowers flavor jams, vinegar, sweets, cream and Provencal stews, and are crystallized for decoration. Dried flowers add long-lasting fragrance to sachets and potpourri. Habitat: Well drained, slightly limy soil, sun.