Whitwam Organics
Sunflower- Mammoth Grey Stripe
Sunflower- Mammoth Grey Stripe
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Sunflower- Mammoth Grey Stripe
Helianthus annuus
The flowering plant Helianthus annuus is native to the Mediterranean region. The 'Mammoth Grey Stripe' (Common Sunflower) is a tall annual with large flowers that can measure up to 8-12 inches (20-30 cm) in diameter and light golden-yellow petals that cover a dark chocolate central disk. Bees, butterflies, and birds are attracted to the beautiful flower heads that are born atop robust stalks, and they make a real statement in the landscape. It's simple to plant. Large seeds with a decent oil content, Grey Stripe are a perfect sunflower for seed harvest.
|
Days to germination |
5-12 days |
|
Days to maturity |
70-100 days |
|
Life cycle |
Annual |
|
Plant time |
Spring |
|
Spacing |
48 inches |
|
Sun |
Full sun |
|
Soil temperature |
70-85 F |
|
Optimum soil P.H |
6.5-7.5 |
|
Height |
8-12 foot |
|
Bloom Time |
Summer (mid, late) |
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Over 800 5-Star Google Reviews
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★★★★★
“All items arrived quickly and well packaged. I usually expect to have one or two live items out of a batch, but they are all thriving. I couldn’t be happier!”
David L.August 2026 -
★★★★★
“My live plants were packed like they belonged in Ft Knox. 😂 They really were packed beautifully. Only one plant, a bee balm, is questionable but signs that it will recover are happening. All in all I am thrilled with my plants and seeds. Some of my coreopsis have already sprouted!”
Jacquie R.September 2026 -
★★★★★
“Plants were ready quick at a good price with great packaging. Very happy with my purchase.”
Will B.May 2026 -
★★★★★
“I’ve ordered seeds from Whitwam Organics 3 or 4 times now. I love the simple packaging, clear planting guidelines, and variety they offer. Great germination rates!! The bare root plants I’ve ordered have come healthy, so healthy that the wild rabbits always approve of my menu upgrades! 😂🐰”
Chanda B.August 2026