Summer/fall bloom
Frost tender
Sow seeds 1/2 inch deep, 1 to 2 inches apart in a sunny location in well-worked garden soil once danger of frost is past. Keep seed bed moist. Seedlings emerge in 5 to 10 days. Keep well weeded and watered while plants are young; mature cosmos can handle hot and dry conditions.
Sow seeds 1 inch apart in a container of seed starting mix, 4 to 6 weeks before last expected frost. Cover 1/2 inch deep, keep moist and provide a good light source. Plant outdoors once weather warms up after gradually acclimating to outdoor conditions. Thin or transplant 8 inches apart when seedlings are large enough to handle.
These free-flowering, long blooming summer flowers fill the garden with vibrant color, producing reliably in all soil types. Sow several times through June for a succession of fresh flowers. Cutting generous bouquets actually prolongs the blooming season. Cosmos pair beautifully with cleome, asters and zinnias.
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