Annual Flower

When to Plant Cosmos in North Carolina

Delicate, daisy-like blooms that dance in the breeze. Cosmos thrive in poor soil and practically grow themselves.

The Short Answer

Cosmos thrive across all three of North Carolina's regions, providing effortless summer color from seed.

North Carolina Frost Dates

Your planting dates depend on which part of North Carolina you're in. Here are the frost date ranges by region:

Region Zones Last Frost (Spring) First Frost (Fall)
Mountains 5b, 6a, 6b Apr 25 - May 15 Sep 25 - Oct 10
Piedmont 7a, 7b Apr 1 - Apr 15 Oct 20 - Nov 5
Coastal Plain 7b, 8a Mar 15 - Apr 1 Nov 1 - Nov 15

Cosmos Planting Schedule for North Carolina

Mountains (Zones 5b, 6a, 6b)

Average last frost: Apr 25 - May 15 · Average first frost: Sep 25 - Oct 10

Start Seeds Indoors
4 wks before frost
Transplant Outside
1 wks after frost
Direct Sow
1 wks after frost

Piedmont (Zones 7a, 7b)

Average last frost: Apr 1 - Apr 15 · Average first frost: Oct 20 - Nov 5

Start Seeds Indoors
4 wks before frost
Transplant Outside
1 wks after frost
Direct Sow
1 wks after frost

Coastal Plain (Zones 7b, 8a)

Average last frost: Mar 15 - Apr 1 · Average first frost: Nov 1 - Nov 15

Start Seeds Indoors
4 wks before frost
Transplant Outside
1 wks after frost
Direct Sow
1 wks after frost

Growing Cosmos in North Carolina

State-Specific Growing Tips

Sow from late April (coast) through mid-May (mountains). Poor soil preferred. Self-seeds for subsequent years.

Recommended Varieties for North Carolina

Sensation Mix, Double Click, Bright Lights.

Common Challenges in North Carolina

Minimal pest or disease issues across all regions.

Growing Tips

Don't over-fertilize — rich soil produces more leaves and fewer flowers. Let some flowers go to seed for next year's crop.

Companion Planting

Plant cosmos alongside these companions for better growth:

Tomatoes Squash

The Bottom Line

Cosmos can be grown successfully in North Carolina with proper attention to regional frost dates and local growing conditions. Timing varies across the state — Mountains gardeners work with a last frost around Apr 25 - May 15, while Coastal Plain sees frost end around Mar 15 - Apr 1. Choose varieties suited to your region, amend your soil based on its specific needs, and monitor for the pests and diseases most common in your area. For exact dates based on your zip code, use our free planting date finder.
Note: All dates are based on NOAA 30-year Climate Normals and represent historical averages, not predictions for any specific year. Always check your local weather forecast before planting frost-sensitive crops. Learn about our data sources.

Last reviewed: March 29, 2026

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