My neighbor started some Mexican sunflowers by seed this spring but then decided she didn't have room for them in a sunny area. She transplanted them into a pot and gave them to me. I left them in the pot to get established and then finally got them in the ground them well into the summer season. Last week they started to bloom.
Also know as tree marigold, Mexican tournesol, Japanese sunflower or Nitobe chrysanthemum, they have beautiful vibrant orange flowers.
I planted the Mexican sunflower plants in an area that previously had an invasive butterfly bush last summer. Bees and butterflies love the flowers on this plant. It is also similar in size the butterfly bush, 5 feet in height in the form of a woody shrub.
In Sri Lanka, where it is called Naththasooriya, it is an invasive species. Much like the butterfly bush the seeds are spread by wind. In the tropics it grows as a perennial, but here it is an annual so I don't think it will be invasive.