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Make Every Day Earth Day - Mammoth Sunflower Seed Packet

$2.99

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Buy More, Save More!

Quantity Discount Final Price Per Packet
4–9 10% off $2.69
10–24 15% off $2.54
25–49 30% off $2.09
50–74 35% off $1.94
75–99 40% off $1.79
100–149 50% off $1.50
150+ 60% off $1.20

Bring giant beauty to your garden while honoring the planet! The Bentley Seed Co. Mammoth Sunflower Seed Packetcombines a cheerful, eco-themed greeting with premium, high-germination Mammoth Sunflower seeds. Known as the classic giant sunflower, this variety produces massive flower heads filled with nutritious seeds.

Whether you're growing cut flowers, or introducing kids to the joys of gardening, these impressive plants are a standout addition to any yard or garden bed.

  • When to Sow: Sow outdoors directly into the garden after all danger of frost has passed in the spring.
  • Planting Depth & Spacing: Prepare loose, well-draining soil in a full-sun location. Plant seeds 1/2 inch deep.
  • Thinning: When seedlings reach 3 inches tall, thin them to 18 to 24 inches apart to give each plant room to develop a strong stalk.
  • Watering & Care: Water regularly during dry periods. Full sun is best for maximum stalk height and bloom size.
  • Brand: Bentley Seed Co. (Cambridge, NY)
  • Variety: Mammoth Sunflower (Helianthus annuus)
  • Lifecycle: Annual
  • Time to Maturity: 75–90 Days
  • Sun Requirement: Full Sun
  • Plant Height: 6' – 9' feet
  • Plant Spacing: 24 inches apart
  • Planting Depth: 1/2 inch
  • Sowing Method: Direct Sow
  • Maintenance: Low
  • Uses: Cut flowers, edible seeds, bird feed, pollinator garden, children's garden projects