Rudbeckia hirta L.

vernacular blackeyed Susan — species · Asteraceae

USDA: RUHI2
GBIF: 3114225
Rank: species

blackeyed Susan (Rudbeckia hirta) — Platephotograph · no rights reservedCC0 · public domain source · iNaturalist ↗

§2Habit & range

Growth habit: Forb/herb
Duration: Annual, Biennial, Perennial
Group: Dicot
Family: Asteraceae Bercht. & J. Presl
Genus: Rudbeckia

§2a

Native status, by region

AK Alaska Introduced
CAN Canada Native
L48 Lower 48 States Native

§2b

County-level range

· 5 counties across 1 state

Legend Native · 5 Introduced · 0 Both · 0 Hover a county for detail.

§3Cultivation specs · USDA

Recorded by the USDA Plant Materials Program.

§3a

Tolerances

Drought: Medium
Shade: High
Moisture use: Medium
Fire: Medium
Salinity: None
Anaerobic: None
CaCO₃: None
Hedging: None

§3b

Climate & soil

Cold tolerance: -23 °F minimum
Frost-free days: 150 min.
Precipitation: 28–65 in/yr
pH range: 6–7
Root depth: 10 in min.
Fertility need: Medium
Soil texture: medium, fine

§3c

Form & growth

Growth form: Single Stem
Growth rate: Rapid
Lifespan: Short
Mature height: 1 ft
Foliage texture: Coarse
Foliage colour: Green
Porosity (summer): Porous
Porosity (winter): Porous
Flower colour: Orange
Fruit colour: Brown
Fire resistant: No
N fixation: None
Toxicity: None

§3d

Reproduction

Bloom period: Summer
Seed abundance: High
Seed begins: Summer
Seed ends: Summer
Spread rate: Moderate
Stratify: No
Seeds / lb: 1,575,760
Propagation: seed

§3e

Use & availability

Commercial availability: Routinely Available
Nursery stock: No
Browse palatability: Low
Graze palatability: Low
Palatable, human: No
Protein potential: Low
Lumber: No
Christmas tree: No

§4Counties, by state

Recorded in 5 counties across 1 state.

Rhode Island view state ↗ 5 N ▾

§5Sources & provenance

USDA PLANTS

Symbol, taxonomy, distribution, cultivation specs, native status. Public domain.

plants.usda.gov/RUHI2 ↗

GBIF Backbone

Canonical taxonomic identity, synonym resolution, cross-refs. CC0.

gbif.org/species/3114225 ↗

Record version

Cached and built locally. Source version on this record:

usda-plants-mt-2026-05-25

fetched 2026-05-25T18:27:19Z