Sunflower Mammoth Grey Stripe HEIRLOOM Seeds

Sunflower Mammoth Grey Stripe HEIRLOOM Seeds

Helianthus annuus

Item #1039

Annual. This giant among sunflowers is a fast grower that can reach 12' tall and produce 10" - 12" flowers! Not fussy about soil, it's very easy to grow and drought tolerant. Grow in a tight row to cover up that not-so-pretty chain link fence or make an attractive screen. Edible gray striped seeds invite birds in the fall (if you don't eat them first!)

Seedling Image


Full sun

Blooms midsummer
to fall

6'-10' tall

Days to Emerge:
10-15 days

Seed Depth:

Seed Spacing:
A group of
3 seeds
every 2'

When 3" tall,
thin to 1
every 2'

When to sow outside: RECOMMENDED. 1 to 2 weeks after average last frost.

When to start inside: 2 to 4 weeks before average last frost.

Artist: Carolyn Crawford

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