Rudbeckia hirta ‘Prairie Sun’

All Rudbeckia species are dye plants (especially R. hirta and R. laciniata) due to the presence of flavonols in their tissues. The inflorescences used alone give orange-yellow colors, while the entire plant provides yellow-green shades.

It is a cultivar derived from Rudbeckia hirta, a short-lived perennial native to the United States.

In the wild in the US, this plant grows in prairies, pastures, and cultivated fields, where it is considered a weed.

The genus name honors Olof Rudbeck (1630-1702) Swedish botanist and founder of the Uppsala Botanic Garden in Sweden where Carl Linnaeus was once a professor of botany.

The species name of hirta means “hairy”, a reference to the short bristles that cover the leaves and stems.

🏆 ‘Prairie Sun’ is an All-America Selection winner in 2003 and a Gold Medal winner at the 2003 Fleuroselect trials in England.

🎨 All Rudbeckia species are dye plants (especially R. hirta and R. laciniata) due to the presence of flavonols in their tissues. The inflorescences alone produce yellow-orange colors, while the entire plant gives yellow-green hues.

🌸 Floral Morphology

The plant itself is a herbaceous perennial, though in many climates it behaves like a short-lived perennial or even an annual.

Its stems are hairy and upright, supporting the flower heads in a way that maximizes visibility to pollinators, while its rough, lance-shaped leaves are adapted to conserve moisture and deter herbivory.

The floral collar is divided into two concentric zones of different colors, a bright yellow border surrounding a central orange-yellow zone.

Interestingly, the hairs on the leaves and stems can also reflect light, slightly reducing leaf temperature and helping the plant survive in open, sunny prairies.

🌱 Reproductive Biology

From a reproductive standpoint, Rudbeckia hirta is prolific. The plant produces small, dry fruits called achenes, which often self-seed around the parent plant.

This self-seeding habit, combined with its long blooming period from mid-summer to early fall, makes ‘Prairie Sun’ particularly resilient in gardens and wildflower plantings.

Its bright yellow flowers are highly attractive to bees, butterflies, and even some birds, highlighting its ecological role beyond simple ornamentation.

🌍 Ecology & Adaptations

Botanically, the cultivar ‘Prairie Sun’ has been selected for its compact stature and consistently vibrant coloration, making it especially suitable for garden borders, prairie-style meadows, and pollinator-friendly landscapes.

Unlike some taller Rudbeckia varieties that can flop over, ‘Prairie Sun’ maintains a tidy, upright habit that is both aesthetically pleasing and practical for small garden spaces.

Its genetic background reflects a balance between wild prairie hardiness and ornamental refinement, giving it both durability and visual appeal.

Other Names:

Black eyed Susan

Origin:

North America