Tithonia, or Mexican sunflower, is one of my very favorite annuals. The large orange, single flowers attract tons of pollinators and butterflies. In the fall, mine are covered with monarchs every night during migration weeks. 5-6' tall, these look like giant, overgrown zinnias. One of the most rewarding annuals to grow from seed. A warm season flower, direct sow into warm soil after danger of frost is over.