SproutSmart
SproutSmart Intelligent Garden Sowing

Black-Eyed Susan

Botanical illustration of Black-Eyed Susan
🌱 60d to harvest Upright

Velvety petals in warm golden amber flare outward from a nearly inky, button-dark center, creating a sunburst bloom that feels lu…

Planting Schedule

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

Crop Dates

MilestoneDate
Start IndoorsJan 23rd
Last FrostMar 6th
Transplant / Sow OutdoorsMar 6th
Harvest BeginsMay 5th
Harvest EndsNov 26th

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.
Botanical illustration of Black-Eyed Susan

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.

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.