Annual Cosmos
Cosmic Red Cosmos is a brilliant heirloom variety that brings vibrant, lipstick-red double and semi-double blooms to any sunny garden with almost zero fuss. These jewel-toned flowers reach 2 inches across on compact plants that grow just 12 to 24 inches tall, making them perfect for borders, containers, or cottage gardens. Reaching maturity in just 50 to 60 days, this care-free annual blooms prolifically throughout the season, drawing pollinators and bringing color from summer through frost.
Full Sun
Moderate
1-11
24in H x ?in W
Annual
High
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What makes Cosmic Red Cosmos truly special is how abundantly it flowers with virtually no deadheading required. The double and semi-double blooms sit on vigorous, well-branched plants that stay manageable in size yet produce an astonishing volume of flowers over a long season. It's the kind of variety that rewards neglect, just give it sun, decent soil, and regular water, and it will repay you with months of brilliant color and constant pollinator visitors.
Cosmic Red Cosmos is grown primarily as an ornamental cut flower and garden display plant. Its long stems and abundant double blooms make it excellent for fresh arrangements, where the vibrant red color adds warmth to mixed bouquets. Gardeners also plant it densely in borders and cottage gardens for continuous color, or in containers for patio displays where its compact height and prolific flowering create impact without sprawl.
You can start seeds indoors 6 to 8 weeks before your last frost date at temperatures between 65 and 85°F. Seeds typically sprout in 7 to 14 days. Transplant seedlings outdoors after the last frost when soil has warmed and nighttime temperatures stay above 60°F.
Harden off seedlings by gradually exposing them to outdoor conditions over 7 to 10 days before planting. Transplant outdoors after all danger of frost has passed and soil temperatures reach at least 60°F. Space plants 10 inches apart.
Direct sow seeds outdoors after the last spring frost when soil has warmed. Press seeds lightly into the soil surface or cover with 1/8 to 1/4 inch of fine soil. Thin seedlings to 10 inches apart once they have true leaves.
Cut flowers for arrangements when the blooms are fully open or just beginning to open, cutting stems in the early morning for longest vase life. Harvest frequently to encourage more flowering throughout the season. Flowers typically last 1 to 2 weeks in a vase with fresh water.
Cosmic Red Cosmos doesn't require pruning due to its naturally compact, branching growth habit. If plants become leggy or overgrown, you can pinch back young stems in early summer to encourage bushier growth, though this isn't typically necessary with this cultivar.
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“Cosmic Red Cosmos represents the heirloom tradition of cosmos breeding, a genus that has been selected and saved by gardeners worldwide for generations. Cosmos sulphureus varieties like this one have been grown and perpetuated because they demonstrate the exceptional vigor and reliability that heirloom gardeners prize. This cultivar carries forward that legacy of easy, abundant flowering that made cosmos such a beloved cottage garden staple, preserved and passed along because it simply works, year after year.”