Sunflower
Helianthus annuus • Asteraceae
🌱 Seed Category
Flower / Grain / Oilseed
🌍 Origin Region
North America (Central and Northern regions)
📅 Days to Maturity
80–120 days; best for direct sowing due to taproot sensitivity; harvest when the back of the flower head turns brown.
🌡️ Hardiness Zones
Zones 2-11; grown as a summer annual in all zones.
About This Seed
The seeds shown are hulled sunflower kernels, appearing off-white or light tan with a teardrop or oval shape and smooth texture. The resulting plant is a tall, upright annual with large, hairy, heart-shaped leaves and bright yellow ray florets surrounding a dark center disk.
Growing Information
Growing Season
Spring to Summer; direct sow after the last frost of the season.
Germination
7–10 days; 70°F to 85°F; light is not required (seeds should be covered); no pre-treatment needed for common varieties.
Planting Instructions
Plant 1 inch deep; space 12-24 inches apart depending on variety size; rows 24-36 inches apart; well-draining soil; pH 6.0 to 7.5.
Sunlight & Water Needs
Full Sun (6-8+ hours daily); moderate watering, though drought-tolerant once established; ensure soil does not become waterlogged.
Companion Plants
Beneficial: Corn, Beans, Squash (Three Sisters variation). Avoid: Potatoes (sunflowers may inhibit their growth via allelopathy).
Special Characteristics
Highly attractive to pollinators like bees and butterflies; seeds are edible and can be used for oil; heavy feeders that improve soil through bioremediation.