top of page
  • Writer's pictureMichele Spence

A How-to-Guide for Planting Cosmos

This wonderful reseeding annual is loved by pollinators that frequent open flowers. Here are the directions to plant Cosmos 'Bright Lights' and 'Sensation' -


If you want a head start, you can plant cosmos indoors 4 to 6 weeks before the last spring frost in trays or pots with a good seed-starting mixture. Seedlings grow fast, so move them into 5-inch pots as soon as they’re 3 or 4 inches tall.

Plant seeds in moist, well-drained soil about ¼-inch deep and 12–18 inches apart after the danger of frost has passed. You can also plant transplants instead of seeds. They also like soil that is not too rich, as rich soil will encourage foliage at the expense of bloom. They can tolerate warm, dry weather.

Depending on the type of flower, cosmos can grow anywhere between 18–60 inches tall.

If you are growing cosmos from seeds, be mindful that it takes about 7 weeks to first bloom. After that, though, your flowers should continue to bloom until the next frost.

If you let the spiky-brown seed heads blow away during the fall, cosmos might sow themselves throughout your garden.

Bright Lights Seed Coverage:

4 G 20 SF

1 Oz 100 SF

Sensation Mix Seed Coverage:

4G 18SF

1Oz 80 SF

8 views0 comments

Recent Posts

See All
bottom of page