Black-Eyed Susan
Rudbeckia hirta — Aster Family
A native biennial wildflower in the Aster Family that blooms in summer suited to dry, sunny conditions.
Planting Guide
When to plant
Sow in late spring. Plants grow vegetatively the first year and bloom in summer of the second year.
Spacing
Space plants 1.1–1.5 feet apart. Closer spacing fills in faster and suppresses weeds; wider spacing gives each plant room to reach full size.
Root system
Roots reach at least 12 inches deep at maturity. Plant the crown at or just below soil level.
Growing Conditions
Sunlight
Full sun — 6 or more hours of direct sunlight per day. This species does not tolerate shade and will thin out or fail to bloom in shadier spots.
Soil & pH
Prefers a wide pH range from acidic to neutral (pH 6.0–7.0). Most average garden soils fall in this range; a quick soil test confirms your starting point.
Watering
Low water needs. Water weekly for the first growing season to establish roots. After establishment, natural rainfall is usually sufficient except during extreme drought. Once established (typically 1 season), it shows strong drought tolerance and can go extended periods without supplemental water.
Seasonal Care
- Deadhead spent flowers regularly to extend bloom period and prevent excessive self-seeding.
- Established plants rarely need supplemental water; deep, infrequent watering beats shallow, frequent watering.
- No active care required. Check if self-sown seedlings appear in early spring.
Wildlife & Garden Value
Ecological benefits
- Member of the Asteraceae (daisy) family — among the most pollinator-rich plant families. The disk florets provide pollen and nectar to hundreds of bee, butterfly, and hover fly species.
Landscaping uses
- Dry slope or hell strip planting where irrigation is difficult or unavailable.
- Rock garden or gravel garden specimen; excellent for low-maintenance landscapes.
Companion Planting
Plants that grow well together
Planting three or more species together attracts a wider range of pollinators and reduces weeding through canopy cover.
Where to Buy Black-Eyed Susan
Buy from specialist native plant nurseries to get the true species rather than a cultivar with reduced wildlife value.
- American Meadows — native seeds and plants
- Prairie Moon Nursery — specialist native plant nursery
- Burpee — seeds with planting instructions