Eye-catching Black-eyed Susans

With a long-lasting and distinctive bloom, along with a catchy name that memorably describes the blossom, Black-eyed Susans are one of the easier landscape plants to identify. Even novice gardeners and children seem to recognize that yellow daisy-like flowers with dark centers are likely to belong to a Black-eyed Susan. Despite that seeming familiarity, there are actually several different species of plants known as Black-eyed Susans, and though there are clear similarities among their flower characteristics, the plants themselves can look very different. 

Rudbeckia fulgida bloom. Photo: Debbie Roos

A clump of Rudbeckia fulgida ‘Goldsturm’. Photo: Eva Munday, CC BY-NC 4.0

The most recognizable of the Black-eyed Susans is Rudbeckia fulgida, a native herbaceous perennial that spreads as wide (or wider) as it grows tall. It has oval shaped leaves adorned with leaf hairs, and resembles Echinacea, or coneflower, another long blooming perennial often planted alongside it. Since  Rudbeckia fulgida spreads by both underground rhizome and seed, it will establish wide clumps in the right conditions. Rudbeckia fulgida was named the 1988 NC Wildflower of the Year, and a popular cultivar of this species ‘Goldstrum’ was named the 1999 Perennial Plant of the Year.  ‘Goldstrum’ is slightly more compact than the species and has larger blooms.  

 Rudbeckia hirta is more upright that R. fulgida, growing to a height of up to 4 feet tall, but spreading less than 2 feet. The color of the flowers may be yellow, orange, or various shades of red. Though also commonly known as Black-eyed Susan, this species is also referred to on occasion as Gloriosa Daisy.  Also native, R.hirta will reseed itself fairly freely; however, they are not difficult to remove if they sprout somewhere they are not wanted.

Rudbeckia hirta comes in yellow, orange, and various shades of red.

Rudbeckia triloba is sometimes referred to as Brown-eyed Susan. Like R.hirta, it is upright more so than spreading, growing as tall as 5 feet with a spread of only about 18 inches. It tends to be a rather short-lived perennial and may only last 2-3 years in a garden before disappearing. It does re-seed fairly liberally, however, so it may pop up in a new spot in the garden to continue its residence.

Rudbeckia triloba is sometimes referred to as ‘Brown-eyed Susan.’

The flower stalks of Rudbeckia maxima stretch as high as seven feet tall.

Finally, there’s a Black-Eyed Susan for those who like their flowers head-high! Rudbeckia maxima, also called Giant Brown-eyed Susan and Cabbage-leaf Coneflower, produces tall flower stalks that stretch as high as 7 feet tall. The leaves are vaguely oval shaped, as are the other members of the genus, but are large and generally clustered tightly toward the lower portion of the plant, forming a clump resembling cabbage. The center of the R. maxima flower stands prominently above the petals, which tend to rest flat or point slightly downward. The overall effect is similar to the plant known as Mexican hat, Ratibida columnifera, so named for its resemblance to the sombrero.    

Rudbeckia of all types will perform best in full sun, though it will tolerate partial shade. All species are tolerant to some degree of hot, humid conditions and are quite drought tolerant once established. Each can be found loaded with various species of butterflies and bees during their bloom period, and each feeds birds via seedhead long after their bloom concludes. Surely you can find space in your garden for at least one!

Matthew Stevens is the County Extension Director and Horticulture Agent for North Carolina Cooperative Extension’s Pitt County Center.  If you have questions about this article or gardening in general, please contact the Pitt County Extension Master Gardeners at [email protected] or 252-902-1705.