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Black Mammoth Sunflower is a towering annual that reaches 8 to 10 feet tall, crowned with dinner-plate-sized flower heads up to 12 inches across. The blooms display a striking contrast: bright yellow petals radiating from deep, silky black centers packed with edible seeds. Growing from zones 2 to 11 and reaching maturity in 100 to 109 days, this cultivar combines dramatic garden presence with practical productivity, rewarding gardeners with both visual spectacle and a substantial seed harvest.
Full Sun
Moderate
2-11
120in H x ?in W
—
High
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At 8 to 10 feet tall, Black Mammoth commands attention in any garden space, delivering flower heads that span a full foot in diameter. The color contrast is genuinely stunning: golden petals frame centers so dark they're nearly black, creating an almost jewel-like appearance that stops visitors in their tracks. These aren't just beautiful; the seed heads fill with edible seeds that birds and gardeners alike find irresistible, making this variety both ornamental and productive.
Black Mammoth sunflowers are grown primarily as ornamental display flowers that bring dramatic height and visual impact to gardens. The mature seed heads provide a bountiful harvest of edible seeds suitable for snacking or bird feed, giving the plant dual value beyond its striking appearance.
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Direct sow Black Mammoth sunflower seeds outdoors after the last frost date when soil temperatures reach 50 to 75 degrees Fahrenheit. Push seeds into the soil at the recommended depth and thin seedlings to the proper spacing once they emerge.
Black Mammoth sunflowers reach harvest maturity in 100 to 109 days from planting. The seed heads are ready when the back of the flower head turns brown and the petals begin to dry and fall away. Cut the entire head with several inches of stem attached and hang it upside down in a warm, dry location to finish drying. Once fully dry, rub the head gently to release the seeds for storage or consumption.
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