Mexican Tarragon has glossy green leaves and bright yellow flowers. The flowers are purely ornamental, while the leaves are licorice scented and flavored. Mexican Tarragon is an ingredient in Mexican and Southwestern cuisine. Mexican Tarragon holds up well in warmer climates, making it a good substitute for French Tarragon, which withers quickly in heat. Mexican Tarragon is an excellent choice for spicy foods as the flavor is stronger and more robust than French Tarragon. The flavor breaks down more quickly when heated, so it is best to add it at the end of cooking. Mexican Tarragon blooms in the summer and fall when all other herbs are waning.