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Russian Mammoth Sunflower | Helianthus annuus (Seeds, 25 Count)

The Russian Mammoth Sunflower is the classic variety for growing giant sunflowers, with towering plants that can reach up to 16 feet tall and enormous golden blooms measuring 10–14 inches across. These cheerful giants make a bold statement in the garden while attracting bees, butterflies, and birds. Perfect for backdrops, children’s gardens, or cutting, the plants are easy to grow and quick to impress.

Growing Russian Mammoth Sunflower (Seeds)

  • Light: Full sun is essential for maximum height and flower size.

  • Soil: Prefers rich, well-draining soil; amend with compost for best growth.

  • Water: Moderate water needs; water deeply but infrequently to encourage strong root systems.

  • Sowing: Direct sow outdoors after the last frost, ½ inch deep and 12–18 inches apart.

  • Bloom Time: Flowers in about 80 days after sowing.

  • Bloom Size: 10–14 inches across.

  • Stem Length: 18–24 inches.

  • Height: 10–16 feet (average 10–12 feet).

  • Hardiness: Hardy annual.

Shipping Info
You will receive one packet containing 25 Russian Mammoth Sunflower seeds. Seeds are carefully packaged for freshness and ready to sow upon arrival.

 

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