How-to Guide
How to Grow Black-Eyed Susans
The short answer
Black-eyed Susan (Rudbeckia hirta) is technically a biennial or short-lived perennial, hardy in USDA zones 3a-8b, that blooms the first year when seeded in early spring — which is why many gardeners treat it like an annual. NC State Extension recommends full sun (6+ hours) to partial shade and moist, well-drained clay, loam, or sandy soil with neutral to acidic pH.
Flowers open in midsummer and, with deadheading, keep coming into mid-fall. Individual plants may fade after a season or two, but the plant freely self-seeds and usually remains in the garden on its own.
What kind of plant is it?
Rudbeckia hirta is listed by NC State Extension as a biennial or short-lived perennial. Because it blooms in its first year from early-spring sowing, it behaves like an annual, then persists in the garden by dropping seed. If you want a longer-lived, clump-forming black-eyed Susan, other Rudbeckia species fill that role; R. hirta's strategy is seed, not longevity.
The species name hirta means 'hairy,' for the short stiff hairs on leaves and stems. Flowers carry 10 to 20 orange-yellow to red rays around a dark purplish-brown central cone.
Sun, soil, and water
Full sun (6 or more hours of direct light) gives the best bloom; plants also perform in partial shade. They accept clay, loam, or sandy soil as long as it is moist but well drained, with neutral to acidic pH, and show moderate resistance to drought, salt, and deer once established.
When and how to plant
- 1Sow seed in early spring — Seed is the recommended way to start Rudbeckia hirta, and early-spring sowing produces flowering plants the same year.
- 2Or set out transplants — Plant nursery starts in spring after frost in full sun, watering until established.
- 3Let it re-sow — Leave some late seed heads standing; the plant freely self-seeds and usually maintains its presence in the garden year to year.
Deadheading and season care
Flowers first mature in midsummer, and with regular deadheading bloom continues into the middle of fall. In late fall you can either cut plants back with other spent perennials or leave the final seed heads to feed birds and re-sow the patch — just remember that a tidy fall cleanup also removes next year's volunteer seedlings.
Common problems
- Powdery mildew can coat leaves, especially in crowded plantings with poor air flow.
- Snails and slugs damage young plants and lower leaves.
- Individual plants dying out after a year or two is normal for this short-lived species — rely on self-sown seedlings for continuity.
Sources
Reviewed 2026-07-18. We cite university Extension, government, and established horticultural sources — and never invent pesticide rates or dangerous treatments.
- North Carolina Extension Gardener Plant Toolbox — Rudbeckia hirta (Black-Eyed Susan) — Zones 3a-8b; biennial or short-lived perennial that blooms first year from early-spring seed; full sun to part shade; moist well-drained soil; midsummer to mid-fall bloom with deadheading; freely self-seeds; susceptible to powdery mildew, snails, slugs