Mammoth Sunflower Seeds

Organic, Heirloom

This giant among sunflowers is a fast grower whose single stalk can reach 12' tall and produces one 10"-12" flower! Not fussy about soil, it's very easy to grow and drought tolerant. Grow in a tight row to make an attractive screen. Sow monthly for continual bloom into fall. Edible, gray-striped seeds invite birds in the fall (if you don't eat the seeds first!).
Now available in larger packet!
  • Conventional Heirloom #1039 - 8 grams
  • $1.99
  • -+
  • Organic Heirloom #2019 - 4 grams
  • $2.29
  • -+
  • Organic Heirloom Large Packet #7501 - 12 grams
  • $4.59
  • -+

Botanical Name: Helianthus annuus

Family: Asteraceae

Native: North America

Hardiness: Annual

Plant Dimensions: 6'–12' tall

Variety Information: Up to 12"-wide flowers with yellow petals and a brown center. Single type.

Exposure: Full sun

Bloom Period: Summer to frost

Attributes: Attracts Pollinators, Cut Flower, Drought Tolerant, Heat Tolerant

When to Sow Outside: RECOMMENDED. 1 to 2 weeks after your average last frost date.

When to Start Inside: 2 to 4 weeks before your average last frost date. Sunflowers are senstive to root disturbance; sow in biodegradable pots that can be planted directly in the ground.

Days to Emerge: 10–15 days

Seed Depth: ¼"–½"

Seed Spacing: A group of 3 seeds every 24"

Thinning: When 3" tall, thin to 1 every 24"

Harvesting: Seeds are ready to harvest when the back of the head has dried and turned brown, about 4 weeks after the flowers have been pollinated. Petals will have wilted and fallen off, and the seeds will be plump, and colored white with gray/black stripes. Seeds ripen around the outside of the flower first; the ones in the center will ripen last. Average yield is approximately 1 pound per head.

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Mammoth Sunflower Seeds Reviews

2 reviews
A towering beauty and a hit with the birds
Review star icon Review star icon Review star icon Review star icon Review star icon Jul 23, 2018
Our wild lovebirds of Phoenix anxiously await the emergence of these tasty seedheads every July.. August.. September.. and October. Successive sowings of this reliable producer will guarantee enough for the birds - and enough for you, too! Large, meaty seeds from vibrant, mesmerizing and cheerful flowers. Strong stems too, which make great supports for Grandpa Ott's morning glories and moonflowers as well!
Ariel L Driver

WOW
Review star icon Review star icon Review star icon Review star icon Review star icon Aug 11, 2020
While most didn't reach 12 feet tall, more like 9-10, I had at least two that were huge. The pollinators LOVED them. I grew twelve plants, and during the 2-3 weeks they were blooming, they were quite the sight in my garden! I am anxious to try the seeds, although if truth be told I grew them primarily for my chickens and the pollinators. I grew them in poor soil, didn't water them, and half of them (I planted them early) were hit with a hard frost in May. I had covered them with cloches, but I think it provided minimal protection. They had a great germination rate, but I started them all indoors.
Anna

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