How to grow Cosmos

How to grow Cosmos

Cosmos (Cosmos bipinnatus)

Cosmos are a great option for beginner gardeners as they require minimal effort. These highly productive flowers have the cut-and-come-again quality, which means that the more you cut, the more they will bloom. Their delicate and airy appearance makes them an excellent addition to any garden or bouquet.


Plant type: annual

Height: 36-42”

Site: full sun

Days to maturity: 75-90 days

Plant spacing: 9”-12”

Pinch: when 12” tall

Kids, Pets and Deer: non-toxic, deer resistant

Indoor & Pots: not suitable for pots


How to Grow:

Transplant: sow 5-7 weeks before last frost, covering the seeds lightly. Harden off and transplant outdoors after all danger of frost has passed. 

Direct seed: sow after last frost, once the soil has warmed up and cover up lightly.

Germination: 7-10 days at 68-72°F (20-22°C)


Harvesting/Vase Life:

Harvest when the petals are just opening, but not yet flattened. Individual blooms don’t last long in the vase, about 4-6 days, but each stem is loaded with multiple blossoms that open over a period of a week.

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