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SproutSmart™ Intelligent Garden Sowing

Prairie Sun

Family: Asteraceae Flower
Zone 6b Save Garden

Planting Schedule

Add Prairie Sun to your garden to build a schedule and get reminders.

Sun-warmed petals unfurl in a golden halo around a velvety, inky center—Prairie Sun Black-eyed Susan brings bold, radiant color to the garden from early summer into fall.

The blooms are richly textured, with sturdy, upright stems that hold their form and a daisy-like presence that feels both lively and refined. Grow it for long-lasting landscape impact, striking cut-flower charm, and effortless pollinator appeal that turns sunny borders into a living tapestry.

Light: Full SunMaturity: 90 DaysHabit: Upright

Botanical illustration of Prairie Sun

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

Crop Dates

MilestoneDate
Start IndoorsDirect Sow
Last FrostApr 25th
Transplant / Sow OutdoorsApr 25th
Harvest BeginsJul 24th
Harvest EndsOct 16th

Crop Details

TraitValue
Days to Maturity90
Sun RequirementsFull SunFull sun
Growth HabitUpright
Support NeededNone
Planting DepthNormal
Germination Temp (°F)70
Min Soil Temp (°F)55
Min Night Temp (°F)40
Harden Off (days)Not Required

Frequently Asked Questions

How do I prevent and treat powdery mildew on Rudbeckia hirta (Prairie Sun)?
Rudbeckia hirta commonly gets powdery mildew in late summer, especially when nights are humid and airflow is poor. At the first white, dusty patches, remove the worst leaves and water at the soil line (not overhead), then improve spacing and airflow around plants. If it keeps spreading, spray with a labeled fungicide for powdery mildew, following the label’s timing and reapplication interval.
How often should I water Prairie Sun Rudbeckia hirta during the main growing phase?
During active growth (after establishment), keep the soil consistently evenly moist but never soggy—aim for about 1 inch of water per week from rain and irrigation combined. Water deeply when the top 1–2 inches of soil feel dry to the touch, and let excess water drain; Rudbeckia hirta dislikes waterlogged soil. Once plants are established, you can stretch watering a bit, but don’t let them dry out completely during bloom.
How can I tell when Prairie Sun (Rudbeckia hirta) is ready to harvest?
For cut flowers, harvest when the central disk florets are fully developed and the bright yellow-orange rays are at their peak color, usually around day 90. Choose blooms that are just starting to open (fresh and firm) rather than those with browned, dried centers. If you’re harvesting seed, wait until the flower heads turn dark and the seeds look mature, then cut heads before they fully shed.

Today's Conditions

Outdoor planting for Prairie Sun in Zone 6b typically begins around 2026-04-25. Wait until soil reaches at least 55°F before transplanting Prairie Sun.

Garden Alerts

In Zone 6b, the average last spring frost is around April 25. Watch soil temperature before transplanting Prairie Sun.

Today's Conditions

Outdoor planting for Prairie Sun in Zone 6b typically begins around 2026-04-25. Wait until soil reaches at least 55°F before transplanting Prairie Sun.

Garden Alerts

In Zone 6b, the average last spring frost is around April 25. Watch soil temperature before transplanting Prairie Sun.

Sowing Tips

Transplant Conditions

Wait until soil reaches 55°F and nights stay above 40°F before moving outdoors.

Expert Note

Sow where they’ll live or direct-sow outdoors for best results—Rudbeckia can transplant, but seedlings establish fastest with minimal root disturbance.