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4.9
Rated 4.9 out of 5 stars
25

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Diablo Cosmos Seeds

Diablo Cosmos Seeds

$3.49
~0.5 g (~60 seeds)
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Free shipping on orders over $79

Product Details

Vibrant, bold blossoms on tall stems make a big statement in the garden. Cosmos put on a big show from midsummer until first fall frost, providing pollen and nectar for bees, hummingbirds, and butterflies. Grows loads of cut flowers for your bouquets. A great choice for wildflower areas, as they are drought tolerant and practically care-free. A 1974 All-America Selections winner.

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  • Variety Info
  • Sowing Info
  • Growing Info

Variety Info

Family: Asteraceae

Type: Cosmos (Learn more)

Native: Mexico

Hardiness: Annual

Exposure: Full sun

Bloom Period: Summer to frost

Plant Dimensions: 4'–5' tall

Variety Info: 1–1½" bright, scarlet/orange blossoms

Attributes: Attracts Hummingbirds, Attracts Butterflies, Attracts Pollinators, Cut Flower, Drought Tolerant

Sowing Info

When to Sow Outside: RECOMMENDED. 1 to 2 weeks after your average last frost date, and when soil temperature is at least 60°F.

When to Start Inside: 4 to 6 weeks before your average last frost date.

Days to Emerge: 5–10 days

Seed Depth: Barely cover

Seed Spacing: A group of 3 seeds every 12"

Thinning: When 1" – 2" tall, thin to 1 every 12"

Growing Info

Harvesting: For longest vase life, cut stems just as flower buds begin to open.

4.9
Rated 4.9 out of 5 stars
Based on 25 reviews
Total 5 star reviews: 22 Total 4 star reviews: 3 Total 3 star reviews: 0 Total 2 star reviews: 0 Total 1 star reviews: 0
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25 reviews
  • John W.
    Verified Buyer
    Rated 5 out of 5 stars
    Mar 9, 2025
    5 Stars

    The Cosmos seeds are greatness! The colors are bright and beautiful. Butterflies love them! Bees too! Butterfly populations have decreased by 20 percent. Bee populations are down as well. Help them recover today!

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  • Kori H.
    Verified Buyer
    Rated 5 out of 5 stars
    Jan 22, 2025
    5 Stars

    These are amazing! Pick a sunny spot. Throw out the seeds a week after your last frost and enjoy the show! Plant early for blooms all summer. Sow again in June for blooms all fall. Thousands of flowers and the butterflies loved them!

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  • Dan L.
    Rated 5 out of 5 stars
    Oct 24, 2024
    5 Stars

    Review Update! The resolution of the photo in my previous review was very poor. This time I hope the photos are clear. My review of the Diablo Cosmos is the same; it is a fantastic flower that grows BIG. I grew them in small pots for the patio not anticipating the height of 8’. Highly recommend this but will definitely plant in a different location or container next year.

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    Which best describes you as a gardener? Intermediate
  • Dan L.
    Rated 5 out of 5 stars
    Oct 23, 2024
    5 Stars

    An amazing Cosmos! They grew 6-7’ tall in small pots on the patio.

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    Which best describes you as a gardener? Intermediate
  • Loris M.
    Verified Buyer
    Rated 5 out of 5 stars
    May 4, 2024
    5 Stars

    I planted Cosmos awhile back and have more sprouting to add to the garden. They are a lovely flower though good or bad seemed to be a trap crop ...that kept the aphids off my broccolli!

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    Which best describes you as a gardener? Beginner
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Diablo Cosmos Seeds

Diablo Cosmos Seeds