Greetings, fellow plant enthusiasts. We are the collective known as Black-eyed Susans, a name you have given to a vibrant group of primarily North American perennials. To you, we are beloved garden staples, but from our perspective, we are distinct species with unique adaptations, growth habits, and requirements. Choosing the "right" one is about understanding which of us will thrive in the specific conditions you can provide. Let us introduce ourselves.
I am the one most commonly recognized as the "Black-eyed Susan." My botanical name is Rudbeckia hirta. My defining characteristic is my life cycle: I am typically a biennial or short-lived perennial. This means I will focus my energy on producing a magnificent display of large, golden-yellow flowers with a dark brown central cone in my second year, after which I may decline. My leaves and stems are covered in coarse hairs (hirta means "hairy"). I excel in meadows, cottage gardens, and any sunny spot with well-drained soil. If you seek a plant that will readily self-seed to create a naturalized, ever-changing display, I am an excellent choice. However, if you desire a long-lived, permanent clump that returns reliably for many years, you might consider one of my cousins.
For gardeners seeking steadfast perennial performance, look to Rudbeckia fulgida and its cultivars, especially R. fulgida var. sullivantii 'Goldsturm'. We are true perennials, forming dense, expanding clumps through rhizomatous roots. Our flowers are slightly smaller than those of R. hirta, but we produce them in incredible profusion from midsummer well into autumn. Our foliage is glossier and less hairy. We are the workhorses of the sunny border, providing structure and relentless color year after year. We prefer consistent moisture but are quite adaptable. If your goal is a low-maintenance, long-lasting ground cover or border plant that will fill a space reliably, we are the right variety for you.
I am Rudbeckia triloba, the "Brown-eyed Susan." I offer a different form and texture. Rather than forming a tight clump, I grow as a bushy, branching plant with many smaller, charming flowers. My basal leaves are often three-lobed (hence triloba). I am also a short-lived perennial or biennial, but I self-seed generously. I bring a lighter, more informal feel to the garden, perfect for the middle or back of a border where my slender stems can wave in the breeze. I can tolerate a bit more shade than my relatives. If you appreciate a more natural, "wildflower" aesthetic and want a plant that will gently move around your garden, I am your ideal candidate.
For a dramatic statement, consider me, Rudbeckia maxima, the Great Coneflower. My most striking feature is not my yellow petals, but my exceptionally tall, grayish-blue, cabbage-like basal leaves and the towering flower stalks that rise 5 to 7 feet high, topped with drooping petals and a prominent, cylindrical dark central cone. I am a bold architectural plant that commands attention. I am a perennial that thrives in full sun and can tolerate moist, even occasionally wet, soils. If you have a large space, a rain garden, or simply wish to add a sculptural, towering element to your landscape, I am the unmistakable choice.
I am Rudbeckia subtomentosa, the Sweet Black-eyed Susan. My claim to fame is the slight scent of vanilla from my foliage when crushed (subtomentosa means "somewhat hairy"). I am a sturdy, clump-forming perennial that does not spread aggressively by rhizomes. I produce an abundance of medium-sized flowers on well-branched stems, making me an excellent cut flower. I am very adaptable to various soil types, including clay, as long as the site is sunny. For a well-behaved, fragrant, and prolific perennial that will form a handsome clump without taking over, I am the perfect selection.
