This is what I found on line … There are 25 species of rudbeckia, according to the National Garden Bureau. The plant is native to North America — mostly the East and Midwest, although Rudbeckia californica (as the name suggests) is a California plant.
Rudbeckia varieties can be several inches tall to more than 10 feet high. Flower colors range from lemony to bronze. While most flowers resemble daisies with dark centers, some rudbeckia have full, fluffy blossoms.
The plant is a member of the Asteraceae family. There are annual, biennial and perennial rudbeckias. Many eagerly reseed or expand in clumps.
-- "A perfect garden is just a garden to be in-perfection. Mornings to work on it and evenings to pause and look at it." Southeast Michigan, Zone 5a/5b