The Mexican Sunflower (Tithonia Rotundifolia) is a different plant than the better-known Common Sunflower and its developed varieties (Helianthus Annuus). This flower doesn’t produce the same kind of edible seeds, but it does live and thrive just about anywhere it’s temperate. Poor soil, little water and hot sun just make these tough, beautiful flowers even happier, it seems at times.
We have these plants in the full Southern Arizona sunlight for 11-12 hours a day, and all they have done is flourish in temperatures as high as 120 degrees in June and July of 2016. Nary a wilt among them all.
The big bonus is that Tithonia are irresistable to important pollinators like bumblebees, solitary native bees, honey bees, butterflies (Mexican Sunflower is a favorite of the Monarch butterfly) and hummingbirds. And they do well in more temperate climates like the Midwest and Atlantic seaboard, as well. They will need absolutely full sun and little water in those places, however.
In our opinion, you can’t find more trouble-free and effusive color anywhere else. And at the end of the season it will re-seed itself and can be tilled under to improve the soil’s carbon/nitrogen content and its texture. Leaves and flowers are edible as greens, also.