Outsidepride Yellow Tithonia Mexican Sunflower Plant Flower Seed - 500 Seeds Grow Yellow Torch Mexican sunflower seeds in USDA zones 4 - 11 as an annual flowering plant grown from tithonia seeds. Tithonia Yellow Torch will grow to 40 inches tall in no time and produce beautiful yellow 3 inch flowering blooms for your flower garden. If you are looking to attract beneficial insects as well as butterflies and humming birds then you want to plant Mexican sunflower seeds which are heirloom. Plant 2 to 3 Yellow Torch Mexican sunflower seeds per plant to begin growing tithonia plants. All sunflower seeds are produced from open pollinated plants and stored appropriately for optimum germination and establishment.