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Black-Eyed Susan

Family: Asteraceae Flower
Zone 6b Save Garden

Planting Schedule

Add Black-Eyed Susan to your garden to build a schedule and get reminders.

Velvety petals in warm golden amber flare outward from a nearly inky, button-dark center, creating a sunburst bloom that feels luminous even on the calmest days.

Black-Eyed Susan forms sturdy, upright clumps with a graceful, airy presence—its flowers hold their shape and texture beautifully as they sway. Grow it for long-lasting garden color in beds and borders, where its bold, high-contrast blooms make a striking statement from early summer into fall.

Light: Full SunMaturity: 60 DaysHabit: Upright

Botanical illustration of Black-Eyed Susan

Planting schedules and alerts are optimized for Columbus (Zone 6b).

Crop Dates

MilestoneDate
Start IndoorsMar 14th
Last FrostApr 25th
Transplant / Sow OutdoorsApr 25th
Harvest BeginsJun 24th
Harvest EndsOct 16th

Crop Details

TraitValue
Days to Maturity60
Sun RequirementsFull SunFull sun
Growth HabitUpright
Support NeededNone
Planting DepthNormal
Germination Temp (°F)70
Min Soil Temp (°F)45
Min Night Temp (°F)35
Harden Off (days)7

Frequently Asked Questions

How do I prevent and treat powdery mildew on Black-Eyed Susan (Rudbeckia hirta) in humid weather?
Powdery mildew shows up as a white, dusty coating on leaves, usually after warm, humid spells. Improve airflow by spacing plants 12–18 in. apart and watering at the soil line (not the foliage). If it appears, spray with potassium bicarbonate or a labeled fungicide and remove badly affected leaves to slow spread.
How often should I water Black-Eyed Susan during the main growing phase (after seedlings establish)?
Water deeply about 1 inch per week during active growth, then let the top 1–2 in. of soil dry slightly before watering again. In hot, dry weeks you may need 2–3 waterings per week, but always avoid soggy soil since Rudbeckia quickly suffers from root problems. A simple test: if the soil feels dry and crumbly at 1–2 in. down, it’s time to water.
How can I tell when Black-Eyed Susan is ready to harvest?
Harvest cut flowers when the center disk is mostly open and the petals are fully expanded, typically around 60 days from sowing. For seed, wait until the ray petals wither and fall and the central disk turns dark and dry; shake the head gently and harvest when seeds don’t cling loosely. Dry harvested seed heads in a well-ventilated area for 1–2 weeks before storing.

Today's Conditions

Outdoor planting for Black-Eyed Susan in Zone 6b typically begins around 2026-04-25. Wait until soil reaches at least 45°F before transplanting Black-Eyed Susan.

Garden Alerts

In Zone 6b, the average last spring frost is around April 25. Watch soil temperature before transplanting Black-Eyed Susan.

Today's Conditions

Outdoor planting for Black-Eyed Susan in Zone 6b typically begins around 2026-04-25. Wait until soil reaches at least 45°F before transplanting Black-Eyed Susan.

Garden Alerts

In Zone 6b, the average last spring frost is around April 25. Watch soil temperature before transplanting Black-Eyed Susan.

Sowing Tips

Transplant Conditions

Wait until soil reaches 45°F and nights stay above 35°F before moving outdoors. Harden off for 7 days first.

Expert Note

For best uniformity, sow lightly and keep evenly moist until seedlings emerge; thin to stand for sturdy blooms.