I had a single plant come up last year from flowers of the season before, but that single plant got to be about 7 feet tall and had at least 100 blooms on it at one time! I had tried in years past to propagate the seeds from spent flowers and they never germinated, so I basically gave up and bought new seeds every year, when I could find them.

My husband was about to till up the flower bed where the tithonia was when I noticed that there were a lot of seedlings coming up and they looked familiar, to my surprise the tithonia had produced about 500 new flower plants!

I have had trouble posting photos in the past, but here is another try. Hope you are able to see this display of tithonias, they are starting to bloom.

Mechelle

Here is a link that might be useful: Tithonia garden