Description

Mammoth Sunflower is a towering heirloom variety known for its giant flower heads, massive seed production, and impressive height. Producing classic golden-yellow petals surrounding dark centers, these sunflowers are a dramatic addition to gardens, fences, and open spaces where their size and presence can truly stand out.

Highly popular with gardeners and wildlife enthusiasts, Mammoth Sunflowers provide abundant edible seeds that can be roasted for snacks or saved for birds. Their sturdy stalks and large blooms also make them excellent for windbreaks, educational gardens, and striking summer displays.

• Type: Open-pollinated annual flower
• Direct sow: After last frost when soil is warm
• Sun: Full sun
• Spacing: 18–24 inches
• Height: 8–12 feet (can reach 14+ feet in ideal conditions)
• Flower head size: 10–14 inches
• Days to bloom: 80–100 days

Mammoth Sunflowers grow best in fertile, well-drained soil with regular watering during early growth and bloom development. Provide support in windy areas due to their height and heavy flower heads. Harvest seeds when the backs of the flower heads turn yellow to brown and seeds are fully mature and plump.

Additional information