Annual Flower

When to Plant Cosmos in Texas

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

The Short Answer

Cosmos are perfect for Texas's challenging growing conditions — they thrive in heat, tolerate drought, and actually bloom better in poor soil. A zero-maintenance flower for Texas's toughest garden spots.

Texas Frost Dates

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

Region Zones Last Frost (Spring) First Frost (Fall)
North Texas (Dallas) 7b, 8a Mar 10 - Mar 25 Nov 5 - Nov 20
Central Texas (Austin/SA) 8a, 8b Feb 25 - Mar 15 Nov 15 - Dec 5
South Texas (Valley) 9a, 9b, 10a Jan 15 - Feb 10 Dec 10 - Jan 5
Texas Panhandle 6b, 7a Apr 10 - Apr 25 Oct 10 - Oct 25
East Texas 8a, 8b Mar 1 - Mar 20 Nov 10 - Nov 25

Cosmos Planting Schedule for Texas

North Texas (Dallas) (Zones 7b, 8a)

Average last frost: Mar 10 - Mar 25 · Average first frost: Nov 5 - Nov 20

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

Central Texas (Austin/SA) (Zones 8a, 8b)

Average last frost: Feb 25 - Mar 15 · Average first frost: Nov 15 - Dec 5

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

South Texas (Valley) (Zones 9a, 9b, 10a)

Average last frost: Jan 15 - Feb 10 · Average first frost: Dec 10 - Jan 5

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

Texas Panhandle (Zones 6b, 7a)

Average last frost: Apr 10 - Apr 25 · Average first frost: Oct 10 - Oct 25

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

East Texas (Zones 8a, 8b)

Average last frost: Mar 1 - Mar 20 · Average first frost: Nov 10 - Nov 25

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

Growing Cosmos in Texas

State-Specific Growing Tips

Direct sow from March. No fertilizer needed. Full sun. Cosmos bloom through Texas heat that stops most other flowers. Let some flowers go to seed for next year's volunteer crop.

Recommended Varieties for Texas

Sensation Mix, Bright Lights (Cosmos sulphureus — more heat tolerant). Any variety handles Texas conditions.

Common Challenges in Texas

Essentially pest-free. Tall plants may lean in wind — group plantings support each other. The easiest flower you can grow in Texas.

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 Texas with proper attention to regional frost dates and local growing conditions. Timing varies across the state — North Texas (Dallas) gardeners work with a last frost around Mar 10 - Mar 25, while East Texas sees frost end around Mar 1 - Mar 20. 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.

Related Guides

Cosmos Growing Guide National planting guide with all states Texas Planting Calendar All plants for Texas Cosmos in Alabama Alabama planting dates Cosmos in Alaska Alaska planting dates Cosmos in Arizona Arizona planting dates Cosmos in Arkansas Arkansas planting dates
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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