Saguaro cactus (Carnegiea gigantea) blossoms are the state flower of Arizona. The cactus is a very slow growing plant, which may add only 1 to 1 ½ inches in the first eight years of life. The Saguaro grows arms or lateral stems but it may take up to 75 years to produce the first one. Saguaro are very long lived and many found in the desert are 175 years old.