Cosmos bipinnatus is a Mexican native annual that has earned its place in gardens worldwide for its effortless charm and prolific blooming. This low-maintenance flower grows 2 to 4 feet tall on slender, upright stems clothed in feathery, threadlike foliage, producing abundant daisy-like blooms in red, pink, or white with sunny yellow centers from early summer until the first frost. Hardy in zones 2 through 11, cosmos thrives on neglect, tolerating drought and poor soils while attracting butterflies and other pollinators throughout the season. Its showy flowers and ability to self-seed make it equally at home in cottage gardens, naturalized spaces, or annual borders.
12
Full Sun
Moderate
2-11
48in H x 36in W
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Moderate
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Cosmos rewards you by asking so little. Plant it in average, well-drained soil in full sun, and it blooms tirelessly from June until frost without fussing. The deeply cut, fern-like foliage creates an airy, elegant texture that complements almost any garden style, while the abundant flowers feed pollinators throughout the growing season. Because it tolerates both drought and poor soils, cosmos excels in tough spots where other annuals struggle, and deadheading spent blooms encourages even more flowering.
Cosmos is grown primarily as an ornamental annual for cutting gardens, cottage borders, and naturalized meadows. The long, sturdy stems and long vase life of individual blooms make it excellent for fresh flower arrangements. Many gardeners also allow cosmos to self-seed year after year, letting it establish itself as a reliable returning presence in the garden.
No timeline data available yet for this variety.
Start seeds indoors 4 to 6 weeks before your last spring frost date. Sow on the soil surface or just barely cover the seeds, as they benefit from light exposure. Keep soil temperature between 65 and 80 degrees Fahrenheit until germination occurs.
Transplant seedlings outdoors just before your last spring frost date, or once soil has warmed. Space plants according to their mature size, typically 12 to 36 inches apart depending on variety. In windy locations, space taller plants closer together to provide mutual support. Shelter plantings from strong winds if possible.
Sow seeds directly in the garden just before your last spring frost date. Plant on the soil surface or barely cover, as seeds need light to germinate.
Deadhead spent flowers regularly to prolong bloom and encourage continuous flowering. Taller plants that exceed 3 or 4 feet may be cut back to encourage branching and a bushier form. Late-season deadheading can be reduced if you wish to allow some flowers to set seed for natural reseeding the following year.
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“Cosmos bipinnatus hails from Mexico, where it evolved as a sun-loving annual adapted to warm seasons and variable moisture. It reached European gardens in the 19th century and became a beloved cottage garden staple, eventually spreading to gardeners worldwide. Its popularity rests on what seems almost counterintuitive: the less you fuss with it, the better it performs. Unlike plants that reward rich feeding and constant attention, cosmos actually thrives when left to its own devices, which made it an accessible flower for generations of gardeners with limited time or resources.”