gorgeous red dahlia // Dahlia is a genus of bushy, tuberous, herbaceous perennial plants native mainly in Mexico, but also Central America, and Colombia. Related species include the sunflower, daisy, chrysanthemum and zinnia. The dahlia was declared the national flower of Mexico in 1963. The tubers were grown as a food crop by the Aztecs, but this use largely died out after the Spanish Conquest. It was named in honor of Anders Dahl, author of Observationes Botanicae.