SproutSmart
SproutSmart Intelligent Garden Sowing

Lemon Queen

Sunflower
Botanical illustration of Lemon Queen
🌱 70d to harvest Upright

Bright as a pocket of sunshine, Lemon Queen blooms with large, warm lemon-yellow petals that glow above sturdy, upright stems. Th…

Planting Schedule

Add Lemon Queen to your garden to build a schedule and get reminders.

Crop Dates

MilestoneDate
Start IndoorsDirect Sow
Last FrostMay 15th
Transplant / Sow OutdoorsMay 15th
Harvest BeginsJul 24th
Harvest EndsAug 25th

Crop Details

TraitValue
Days to Maturity70
Sun RequirementsFull SunFull sun
Growth HabitUpright
Support NeededNone
Planting DepthNormal
Germination Temp (°F)70
Min Soil Temp (°F)55
Min Night Temp (°F)45
Harden Off (days)Not Required

Frequently Asked Questions


What’s the most common disease or pest problem on Helianthus annuus (Sunflower) like Lemon Queen, and how can I stop it?
Sunflowers (Helianthus annuus) commonly suffer from downy mildew, which shows as yellow patches on the upper leaves and a fuzzy gray-purple growth on the undersides. Keep plants spaced for airflow and water at the soil line (not overhead); remove heavily infected leaves early to slow spread. If conditions stay humid, use a labeled fungicide for downy mildew and follow the label’s reapplication timing.
How often should I water Lemon Queen sunflower during the main growing phase?
During the main growth phase (roughly after the plants establish and before seed fill), keep soil evenly moist but not waterlogged—about 1 inch of water per week depending on heat and soil drainage. Water deeply when the top 1–2 inches of soil dry out, and avoid frequent light sprinkling that encourages shallow roots and leaf disease.
How do I know when Lemon Queen sunflower is ready to harvest after about 70 days?
Harvest when the back of the flower head turns yellow to brown and the bracts start to dry, and the seeds look plump with dark stripes typical of Helianthus annuus. Rub a few seeds—if they detach readily, they’re ready; cut the heads and dry them in a well-ventilated, shaded area for several days before removing seeds.
Botanical illustration of Lemon Queen

Bright as a pocket of sunshine, Lemon Queen blooms with large, warm lemon-yellow petals that glow above sturdy, upright stems. The flower heads are generously full, offering a velvety texture and a bold, cheerful presence that draws pollinators from near and far. Grow it for standout cut-flower impact in the garden and for long-lasting color that enlivens borders, beds, and sunny corners throughout the season.

Sowing Tips

Transplant Conditions

Wait until soil reaches 55°F and nights stay above 45°F before moving outdoors.

Expert Note

For the best blooms, sow where they won’t be transplanted (or start very early) and keep moisture even until establishment, then let plants dry slightly between waterings.