Mammoth Sunflower Seeds – Giant Classic Sunflower

Scientific Name: Helianthus annuus
Hardiness Zone: 2–11 (grown as an annual)
Sunlight Exposure: Full Sun
Water Needs: Moderate to High
Temperature Range: 65–90°F (18–32°C)
Days from Seed to Harvest: 90–110 days (blooms and seeds)

About the Plant

Mammoth Sunflower is a legendary giant sunflower variety known for its impressive height and massive golden blooms that can reach up to 12 inches or more in diameter. Plants can grow 10–14 feet tall, making them a dramatic focal point in any garden. In addition to their beauty, Mammoth Sunflowers produce large edible seeds that are loved by both people and birds.

How to Grow (Simple Steps)

• Direct sow seeds outdoors after the last frost, or start indoors 2–3 weeks early.

• Sow seeds 1 inch deep in well-draining soil.

• Ideal soil temperature for germination: 65–85°F.

• Space plants 18–24 inches apart in full sun.

• Water regularly and provide support if needed due to height.

• Harvest seed heads when the back of the flower turns yellow and seeds mature.

Peruvian Garden Inspiration

Mammoth Sunflowers bring strength and abundance to the garden, echoing the bold, sun-filled landscapes and agricultural traditions of the Andes.

Our Mission

We are a small family farm in Mansfield, Ohio, dedicated to sharing Peruvian traditions and rare plants with the world. Every purchase helps support our mission to rescue and care for abandoned cats.

“Peruvian Roots, American Blooms.”
Peruvian Roots Farm