Black Eyed Susan is a biennial native to the Eastern half of North America that produces yellow daisy-like flowers 3″ diameter (7 cm). A showy addition to any garden it is easy to grow and establish. It loves full sun and well drained soil and will complete it’s life cycle in two years. But, it repopulates itself via self-seeding.
Now lets take a look at the reference table with some key facts about Black Eyed Susan:
Black Eyed Susan Reference Table
| Scientific Name | Rudbeckia hirta |
| Common Names | Black Eyed Susan |
| Height | 1-3′ (0.3-1.3 m) |
| Spacing | 12″-24″ (30-60 cm) |
| Sunlight | Full sun, partial sun |
| Soil Type | Clay, loam, Sand |
| Soil Moisture | moist to dry |
| Bloom Time & Duration | Late Spring – Mid Summer, 4-6 weeks. |
| Bloom Color | Yellow |
| Larval Host | Silvery Checkerspot, Bordered Patch, Gorgone Checkerspot butterflies |
| Native Range | Everything East of the Rocky Mountains, USA/Canada |
| Zone | 3-7 |
| Notes: | High wildlife value, Showy, Great Cut-Flower. |
Growing Conditions
Black Eyed Susan grows best in Full sun and well drained soil with medium moisture. Although, it can tolerate slightly moist or slightly dry conditions as well.
If the soil is fertile, it will be quite prolific and vigorous. But, this flower readily grows in ditches and poor soils (mine, for example). It self-seeds heavily in disturbed areas, but due to it’s compact nature doesn’t travel far.
Garden Uses
Black Eyed Susans will bloom for approximately 4 weeks and are very showy. They are a great addition to any border, wildflower garden, micro-prairie, or flower bed. Even though it is short lived, it is easy to grow from seed and Black Eyed Susans will bloom the first year.
Also, not limited to in-ground gardens. Black Eyed Susans can be grown in containers if proper steps are followed.
Did you know that Black Eyed Susans can thrive in clay soil? Find out other clay-loving flowers here!
Cut Flower
Black Eyed Susan is a great plant to grow for cut flowers. The amount of blooms generated is excellent. In my experience they look great in a vase for one of the longest duration.
Native Habitat
Rudbeckia hirta is a natural prairie plant. So, open meadows, roadside ditches, prairies are all where you can find this growing wild. It is also a great plant to forage for seed, as a few seed heads can yield 50-100 seed.
Fauna associations
Insects
Black Eyed Susan is visited by numerous bees, pollinating wasps and flies. It is also host to several butterflies, notably the Silvery Checkerspot, Bordered Patch, and the Gorgone Checkerspot.
Mammals
Foliage of young plants and seedlings are browsed by rabbits. If damage is noticed, you should apply Liquid Fence, which can be found on our recommended products page.
Video Overview
See our complete video profile on this wonderful species!
Black Eyed Susan Identification
Generally found in small to large colonies in open fields and roadside ditches, Black Eyed Susan are readily identifiable by their height, bloom time, leaves and stalk.
Stalk Stem
In the wild it is generally around 2′ tall (60 cm) while in cultivated areas it can reach 3-4′ (1-1.3 m). The round stalk will be light green and covered with white hairs, appearing fuzzy. [1]
Leaves
Leaves are alternate and lanceolate shaped, or oviate. Their size is highly variable, ranging from 2″ long by 1/2″ wide to 7″ long by 2″ wide. The leaves are covered in hair, giving them a rough, but fuzzy feeling when touched. [1]
Flower
Stalks will terminate with a single flower that is approximately 2-4″ diameter, with numerous yellow petals surrounding a central black disc. The central disc may be raised or flat. I have found wild specimens that had reddish coloring at the base of the petals, although it is quite rare. [1]
After blooming for approximately 1 month, the petals will whither and fade. Seeds will form on the disc, which will eventually attract birds – namely gold finches. Although it does not seem to be as preferred a food source as Echinacea or Coreopsis seeds.
Harvesting Black Eyed Susan seeds is quite easy. We’ve written a detailed guide that I highly recommend you check out. We made a ‘new’ process for harvesting all Rudbeckia seed that completely separates the chaff. Click below to see how!
Root
Black Eyed Susan’s have a small tap-root, and no rhizomes.
Purchase Seed
We have ordered a variety of native flower seeds from Everwilde Farms, which you can order right from Amazon through our link on our RECOMMENDED PRODUCTS PAGE. (We may earn a small commission when you purchase through our links, at no cost to you. This helps support our website.)
Variations
There are numerous cultivars and varieties of Black Eyes Susan that are available for seed purchase, or even as plants in garden centers. So, it is quite easy to find one that suits you. But, if you are unsure, you can always read our starter guide to the entire Rudbeckia genus below!
[1] – Duncan, Wilbur H., and Marion B. Duncan. Wildflowers of the eastern United States. Vol. 20. University of Georgia Press, 2005.
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