The showy garden rudbeckias that brighten summer and fall borders are descended from wild plants native mainly to the eastern U.S. All are tough and easy to grow. Blossoms have yellow or orange rays and a raised central cone. Choice cut flowers; cutting also encourages rebloom late in season. Divide perennials when crowded, usually every few years.
eared black-eyed susan
- Zones MS, LS, CS, TS; USDA 7-10.
- Native to moist areas of southeastern Alabama and nearby Georgia and Florida.
- Grows 6 feet high.
- Golden yellow flowers are 2 to 3 inches wide.
- Often needs staking.
- Takes alkaline soils.
- Initially 3 feet tall, 2 feet wide; after a few years, spreads by rhizomes to form a larger clump.
- Branching stems; broadly lance-shaped, 5 inches-long, hairy, dark green leaves.
- Yellow, 2- to 2 inches-wide flowers with a black to brown central cone bloom in summer.
- Selections are more often grown than the species.
- Among the most popular is Rudbeckia f.
- sullivantii 'Goldsturm', bearing 3 inches., black-eyed yellow flowers on 2- to 2 feet stems.
- Some nurseries offer the taller, more variable seed-grown Goldsturm strain.
- Early Bird Gold has an especially long bloom season, running spring to fall.
black-eyed susan, gloriosa daisy
- speciosa (R.
- speciosa), to 2 feet high and 2 feet wide, is native from New Jersey to Alabama and Georgia; it has bright orange-yellow petals surrounding a black cone.
- Its selection 'Viette's Little Suzy' is a dwarf to about 14 inches high and wide, with dark-eyed yellow blooms.
- Biennial or short-lived perennial; often grown as annual because it blooms the first summer from seed sown in early spring.
- Zones US, MS, LS, CS, TS; USDA 6-11.
- To 34 feet tall, 1 feet wide, with upright, branching habit.
- Stems and lance-shaped leaves to 4 inches long are rough and hairy.
- Daisylike, 2- to 4 inches-wide flowers have orange-yellow rays and a prominent purplish black cone.
- Not usually browsed by deer.
- produces 6- to 9 inches., single to semidouble flowers in golden yellow.
- Irish Eyes ('Green Eyes') has 2- to 3 inches., golden yellow flowers with a light green central cone that ages to brown.
- Prairie Sun has golden petals with light yellow tips surrounding a pale green cone.
- Denver Daisy bears large (68 inches.) yellow flowers with a dark cone and a large burgundy eye.
- It is a heavy bloomer that reaches 2226 inches tall.
- Cherokee Sunset has semidouble to double flowers (34 inches.) in a range of yellow, orange, red, bronze, and mahogany.
- It grows 23 feet tall.
For front of border, try lower-growing selections 'Goldilocks' (double flowers) and 'Toto', both 810 inches high; Becky Mix (1215 inches.); 'Sonora' (15 inches.); 'Tiger Eye' (1624 inches high and wide, with unusually profuse bloom), and 'Marmalade' (2 feet.).
- The species grows 10 feet tall, 4 feet wide; it has light green, deeply lobed leaves to 4 inches long and blooms from summer to fall, bearing 2- to 3 inches-wide flowers with drooping yellow rays and a green cone.
- Very heat tolerant.
- More widely grown in gardens are the following three selections.
- Golden Glow ('Hortensia'), to 67 feet tall, is an old favorite that bears bright yellow double flowers 23 inches wide.
- Good summer screen or tall plant for back of borders.
- Does not seed, but spreads rapidly (sometimes aggressively) by underground stems.
- Goldquelle, with double blooms in lemon-yellow, is a less aggressive form growing 3 feet tall, 1 feet wide.
- Autumn Sun ('Herbstonne', often listed as the similar native Rudbeckia nitida) grows to 6 feet tall, 2 feet wide; bears single, 4- to 5 inches-wide flowers with yellow rays and a bright green cone that ages to yellow.
- Large (to 5 inches.) bluish gray leaves form a mound to 23 feet tall and wide.
- In midsummer, 5- to 6 feet stems bear flowers to 3 inches across, with a prominent brown central cone and drooping yellow rays.
- Golda Emanis combines golden foliage that fades to chartreuse as it blooms, producing golden, daisy-like blooms on 7 feet tall stalks.
- Biennial or perennial.
- To about 4 feet tall and as wide, with stiff, much-branched stems and 5 inches-long leaves, some deeply lobed.
- Blossoms to 3 inches wide, with yellow-orange rays and dark brown-purple centers.
- Can be weedy looking.
- Prairie Glow has large, bicolored, yellow and orange-red blooms that make great cut flowers.