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Mammoth Gray Stripe Sunflower
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Mammoth Gray Stripe Sunflower

A Tasty Treat

Enormous yellow flowers measure 14 in. across and yield a whopper crop of seeds! High oil content makes for great roasted flavor. Grows 9-12 ft. tall. 100 DAYS.

For each offer ordered, get 1/4 lb of seeds

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Product Details

  • Botanical Name: Helianthus annuus 'Mammoth Gray Stripe'
  • Height: 9 - 12 feet.
  • Spacing: 2 - 4 feet.
  • Depth: 1 inch.
  • Spread: 15 - 24 inches.
  • Light Required: Full Sun.
  • Color: Orange-yellow.
  • Foliage: Very rough; to 1 foot long heart-shaped green leaves.
  • Blooms: July - September.
  • Days To Maturity: 100 days.
  • Zone: 3 - 9.
  • Germination: 10 - 14 days at 68 - 86 degrees F.
  • Form: Upright, Annual.
  • Flower Form: Bright yellow flowers up to 20 inches in diameter.
  • Soil Requirements: Light, well-drained, dry soil.
  • Growth Rate: Moderate growth rate.
  • Seed Count: Approximately 300 seeds per ounce. 1/4 lb. is approximately 1200 seeds. Sold by weight.
  • Size: 8 - 14 inch flowers.
  • Comments: Will do well in poor soil. Tolerates heat and dry conditions. Average head size is 10 - 15 inches, but have reached 20 inches. Extremely large heads on 9 - 12 foot stalks.


Most times, orders having items with different shipping schedules are held in full until the entire order is ready to ship based on your grow zone.

Plants will be shipped at the proper planting time for your area of the country using the shipping timeframes outlined below. We continually monitor weather conditions for extreme hot or cold and adjust shipping schedules as needed. Due to hot weather conditions, we are unable to ship most plant items in July and August.

2019 Fall Shipping Schedule
1A to 4B 6/18 - 11/1
5A & 5B 6/18 - 11/1
6A & 6B 6/18 - 11/1
7A & 7B 6/18 - 11/1
8A & 8B 6/18 - 11/1
9A to 10B 6/18 - 11/1
Last Order Date All Grow Zones: Oct 28, 2019

Additional Shipping Notes:

The type of product you order or the weather in our area to yours may affect the anticipated shipping schedule, shifting earlier or later, depending.

Trees and shrubs are kept in the nursery row until full dormant for optimum stress protection.

In all cases, we choose the fastest, most efficient way to send your orders via the U.S. Postal Service or FedEx. Large orders or large items may be shipped to you in multiple packages.

Sorry, we cannot ship products to Hawaii, Alaska, APO/FPO or outside the contiguous United States. Please provide a street address as some products are unable to be delivered to Post Office boxes.

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