Black-Eyed Susan — Growing reference
| Scientific name | Rudbeckia hirta |
|---|---|
| Seed germination (days) | 7–14 |
| Soil temperature for germination (°C) | 18.3–21.1 |
| First harvest or flowering (days) | 60–90 |
| Measured from | Seed |
| Plant spacing (cm) | 30.5–61 |
| Mature height (cm) | 45.7–91.4 |
| Mature spread (cm) | 30.5–61 |
| USDA hardiness zones | 3–9 |
| Light | Full sun |
| Water | Low |
| Sowing method | Direct sow |
Growing directions
Direct-sow seeds on prepared soil surface in full sun in early spring or fall, pressing lightly without covering as seeds need light for germination; black-eyed Susan is one of the most reliably beautiful and adaptable native wildflowers of eastern and central North America, blooming with golden-yellow daisy-like flowers with distinctive dark chocolate-brown centers from midsummer through frost. It thrives in lean, dry to moderately fertile, well-drained soil and deteriorates in rich, wet conditions — never amend the soil with heavy fertilizers. A short-lived perennial that self-seeds freely to perpetuate naturally; leave seed heads standing through winter as they are a critical food source for goldfinches and other songbirds. Excellent as a cut flower and as a native companion for grasses and other prairie perennials.
Source and local conditions
Typical planning ranges from OpenPlantDB (CC0). Cultivar, climate, season and growing method can change these values. Confirm the seed label and local guidance before planting.
Source & verification
OpenPlantDB · CC0