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When to Plant Zinnia in Stephens County, TX

Zinnia (Zinnia elegans) is a fast-growing, heat-loving annual that produces bold, dahlia-like blooms from early summer until hard frost. One of the easiest flowers to grow from direct-sown seed, zinnias thrive in hot, dry conditions and are magnets for butterflies and beneficial insects. They make excellent companion plants alongside marigolds in the vegetable garden.

Stephens County, Texas is in USDA Zone 8a. The average last spring frost is April 4 and the first fall frost is November 10, giving you a growing season of approximately 220 days.

At an elevation of 3,055 feet, Stephens County receives approximately 63.4 inches of rainfall annually with predominantly loam soil. Summer highs average 92°F, providing good warmth for Zinnia during the growing season. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Zinnia root diseases.

Annual Blooms in Summer Pollinator-friendly Deer-resistant Good for cutting
Stephens County, TX (Zone 8a) Long season
220 days
Last Spring Frost April 4
220 growing days
First Fall Frost November 10

Stephens County Soil Profile

Soil Type

Loam

Soil pH

6.0-7.0

Drainage

Well Drained

Zinnia Planting Timeline — Stephens County, TX

Zinnia Planting Calendar

Activity When Date Range
Start Indoors March 7 Mar 7 – Mar 21
Transplant Outdoors March 28 Mar 28 – Apr 11
Direct Sow March 28 Mar 28 – Apr 18
Bloom June 6 Jun 6 – Oct 24

Plant 0.3" deep · 12" apart · Rows 18" apart

Month-by-Month Timeline

MonthActivities
January
February
March Start Indoors Transplant Outdoors Direct Sow
April Transplant Outdoors Direct Sow
May
June Bloom
July Bloom
August Bloom
September Bloom
October Bloom
November
December

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

Low — drought tolerant

📅 Days to Maturity

60–70 days

🧪 Soil pH

Needs 5.5–7.5 · Your soil: N/A

🗺️ USDA Zone

Zone 8a

📆 Growing Season

220 days in Stephens County

Growing Tips for Stephens County

Direct-sow after last frost when soil reaches 60°F; seeds germinate in 5-7 days. In zones 3-5 a brief indoor start (4 weeks) is worthwhile but transplant carefully — zinnias dislike root disturbance. Deadhead frequently to extend bloom. Excellent cut flower; harvesting regularly encourages branching. Avoid overhead watering to reduce powdery mildew.

Companion Planting

Good Companions

Avoid Planting Near

  • Fennel

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Zinnia in Stephens County, TX?

Stephens County is in Zone 8a with an average last frost of April 4. Plan your Zinnia planting based on this frost date — see the calendar above for exact timing.

What planting zone is Stephens County, TX?

Stephens County, Texas is in USDA Hardiness Zone 8a. The average last spring frost is April 4 and first fall frost is November 10.

🌱

Your Stephens County Garden Planner — Free

A 22-page printable planner built for Stephens County (Zone 8a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.

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Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Stephens County, TX. Local conditions may vary. Last updated: July 2026.

Sources & credits

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