How To Grow Cosmos From Seed

How To Grow Cosmos From Seed

With bright and colorful daisy-like blooms, Cosmos are a summer garden delight. They're tall, hardy, fuss-free, drought-tolerant, and handle so many types of soil. Cosmos come in many colors and make excellent cut flowers.

Top Cosmo Varieties

Klondyke Orange - Brilliant orange flowers

Dwarf Sulphur Yellow - Buttery yellow flowers, compact and grow up to 18" tall.

Dwarf White - Snow white flowers

Daydream - Pastel pink flowers with dark pink highlights

Sensation Mix - A mix of maroon, pink, white, and lavender flowers

All About Cosmos

Cosmo flowers are 3-5 inches wide and bowl shaped. There are yellow, white, pink, orange, purple, red, and maroon varieties, so you can fill the flower garden with color. Cosmos are tall, often reaching up to 6-feet, and the flowers bloom atop tall, graceful stems. Butterflies, bees, and birds all adore these flowers, too.

Because they grow so tall, Cosmos may need to be staked. Growing them against a building or fence also works wonderfully.

How To Grow Cosmos From Seed

Cosmo plants grow quickly and don't need to be started indoors first.

  1. Plant outdoors in spring after all danger of frost has passed
  2. Choose a location in full sun
  3. Water the planting area first, so pressure of watering doesn't disturb the seeds later
  4. Scatter Cosmo seeds over the soil
  5. Very lightly press the seeds into the soil – this is best done by walking over them. Don't bury them as they need sun to germinate.
  6. Keep the soil moist until the seeds sprout and get established, then water, as needed.
  7. It takes about 7 weeks for flowers to bloom, and then they'll bloom all the way through fall.
  8. Deadhead the flowers after blooming to prevent rapid self-seeding. Otherwise, let them go and they'll come up the following year(s).
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