I have also noticed variability in growth patterns of this species. But then I'm farther north and it is considered to be a more southern type plant. I have about 1/2 dozen plants and I never know at the start of each season which ones will bloom and which won't. So I continue to try to germinate more each year in hope of always having some in bloom.
But they are so worth the effort, don't you think?

they are so worth the effort..I try to germinate the seeds every late winter....love the bluish leaves and the visual effect they have in the garden.
happy gardening!

Gardenlady-have you figured out what magic is required to get them to germinate?

I got seeds of G. Coneflower and plan to sow them. I will report my results. One question I have is this. Will they bloom in partial sun, dappled, like the ordinary coneflowers do or do they need full sun? Anyone tried that?

Mine have been in full sun with well drained moisture retentive soil.

Yes, they'll bloom in part sun-shade, but have less blooms. I deadhead the early blooms for more blooms later. They're good winter sow candidates. Be patient. Mine from seed didn't blooms this year, but will next I hope.

Thanks for the information. I always have to ask because anything that will perform well in part shade is something I need. I think I will do these in full sun and add them to my wintersowing seeds, a list that keeps expanding.

I heard they don't do well in very dry soil. Any comments? We are in drought conditions here and it will determine where I plant them if I'm successful with the seeds. How about heat tolerance? We had 100+ for two months this summer.

They are a more southern type of Rudbeckia so I would think they will prefer your place than mine. I'm thinking that all Rudbeckia prefer the more moister environment, on the edge of a swampy ground perhaps.

I cut off some stalks with the seed heads attached and threw them into the edge of the woods where I throw stuff to self compost. Several plants have self seeded there. I do not want them and have not watered them, but they stubbornly continue to grow.