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Rubenza Cosmos Seeds

Rubenza Cosmos Seeds

Regular price $2.69
Sale price $2.69 Regular price
~0.3 g (~29 seeds)
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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.

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"

4.3
Rated 4.3 out of 5 stars
Based on 12 reviews
Total 5 star reviews: 9 Total 4 star reviews: 1 Total 3 star reviews: 0 Total 2 star reviews: 0 Total 1 star reviews: 2
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12 reviews
  • 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.

    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.

  • 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!

    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!

    Which best describes you as a gardener? Professional
  • Joy
    Rated 5 out of 5 stars
    May 27, 2025
    5 Stars

    They are in the soil outside and the rain is failing. Hoping for bright cosmos in a few weeks