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Botanical illustration of Rubenza cosmos showing several deep red, yellow-centred flowers with feathery green foliage on slender stems, one bloom visited by a hoverfly, against a plain white background.
Line drawing of a young cosmos seedling with a slender central stem and paired feathery leaf branches, labeled
Cosmos Rubenza seed packet with red flowers illustration and botanical information
Close-up of a Rubenza cosmos flower with deep crimson-to-magenta petals and a bright yellow center, backlit by sunlight against a blurred green garden background, labelled
Botanical illustration of Rubenza cosmos showing several deep red, yellow-centred flowers with feathery green foliage on slender stems, one bloom visited by a hoverfly, against a plain white background.
Line drawing of a young cosmos seedling with a slender central stem and paired feathery leaf branches, labeled
Cosmos Rubenza seed packet with red flowers illustration and botanical information
Close-up of a Rubenza cosmos flower with deep crimson-to-magenta petals and a bright yellow center, backlit by sunlight against a blurred green garden background, labelled
4.1
Rated 4.1 out of 5 stars
16

Botanical Interests

Rubenza Cosmos Seeds

Rubenza Cosmos Seeds

Cosmos bipinnatus

$2.69
~0.3 g (~29 seeds)

Members save $0.26

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29 seeds

Free shipping on orders over $79



Product Details

Deeply colored 3" blooms are beauteous in contrast when paired with white flowers and silver-foliage plants. A Fleuroselect Novelty award winner, this cosmos is a real standout in the garden or a vase, and butterflies love them, too. Blooms start out red-wine colored and turn to dusky rose as they age. Growing cosmos is an easy way to add color to your garden, as they require little attention and are drought tolerant.

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  • Variety Info
  • Sowing Info

Variety Info

Family: Asteraceae

Type: Cosmos (Learn more)

Native: Mexico and Arizona

Hardiness: Annual

Exposure: Full sun

Bloom Period: Summer to frost

Plant Dimensions: 24"–32" tall, about 28" wide

Variety Info: Flowers up to 3" start out deep wine-red, turning to rose as they age.

Attributes: Attracts Butterflies, Attracts Hummingbirds, 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.

Sprouts in: 5–10 Days

Plant Seeds (Depth): Barely cover

Space Seeds: A group of 3 seeds every 12"

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

4.1
Rated 4.1 out of 5 stars
Based on 16 reviews
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16 reviews
  • Pablo R.
    CA, United States
    Verified Buyer
    Rated 4 out of 5 stars
    Sep 11, 2026
    Lovely delicate looking flowers

    Love the color when it’s a fresh new bloom. Only planted a few to go into my new garden bed. But definitely going to be planting many more come spring. Can’t wait!

    Was this helpful?
    Which best describes you as a gardener? Intermediate
    Who do you grow for? Yourself
    How do you prefer to grow? Raised Bed
    EG Profile picture for Epic Gardening
    Epic Gardening
    Sep 13, 2026

    Hey Pablo,

    We're so happy to hear that your Rubenza Cosmos Seeds are looking absolutely lovely in your new garden bed! Those delicate blooms sound gorgeous, especially when they're fresh and new. We love that you're already planning to plant many more come spring - that's the kind of enthusiasm we love to see! Thanks so much for being part of the growing community! Keep on growing 🌻

  • Miriam T.
    Verified Buyer
    Rated 5 out of 5 stars
    Aug 30, 2024
    5 Stars

    I love the color these Rubenza cosmos add to my small rooftop garden. Even though they are in full sun, they can withstand not being watered every few days.

    Was this helpful?
    Which best describes you as a gardener? Intermediate
  • Loris M.
    Verified Buyer
    Rated 5 out of 5 stars
    Feb 18, 2024
    5 Stars

    Great product resource.

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  • Lily ..
    Rated 5 out of 5 stars
    Jan 28, 2024
    5 Stars

    I really love the color of these. As described, they do in fact start out very vibrant, before fading beautifully into a duskier pink. Among my favorite flowers in the garden!

    Was this helpful?
    Which best describes you as a gardener? Intermediate
  • Peggy G.
    Rated 5 out of 5 stars
    Dec 28, 2023
    5 Stars

    I did landscaping yrs ago, retired(both careers), couldn't "move earth"last yr (2023) so I literally threw seeds... Cosmos and Zinnias well it was like a Monet painting!

    Was this helpful?
    Which best describes you as a gardener? Professional
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Botanical illustration of Rubenza cosmos showing several deep red, yellow-centred flowers with feathery green foliage on slender stems, one bloom visited by a hoverfly, against a plain white background.

Rubenza Cosmos Seeds

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