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When to Plant Sunflower in Terrell County, TX

Sunflowers are tall, cheerful annuals grown for their edible seeds and as pollinator magnets. They come in sizes from 2-foot dwarfs to 12-foot giants.

Terrell County, Texas is in USDA Zone 7b. The average last spring frost is March 2 and the first fall frost is November 27, giving you a growing season of approximately 270 days.

At an elevation of 3,434 feet, Terrell County receives approximately 45.8 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 96ยฐF, so Sunflower may need afternoon shade and extra watering during peak heat. Sandy soil warms quickly in spring โ€” great for early planting โ€” but Sunflower will need more frequent watering and organic matter to retain nutrients.

Terrell County, TX (Zone 7b) Year-round
270 days
Last Spring Frost March 2
270 growing days
First Fall Frost November 27

Terrell County Soil Profile

Soil Type

Sandy Loam

Soil pH

7.3-8.4

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (143 days to spare)
Start indoors: Jan 1 Transplant: Mar 5 🍅 Harvest: May 14 – Jul 2
Recommended (50%) ✓ Fits season (137 days to spare)
Start indoors: Jan 12 Transplant: Mar 16 🍅 Harvest: May 25 – Jul 13
Safe Start (90%) ✓ Fits season (130 days to spare)
Start indoors: Feb 1 Transplant: Apr 5 🍅 Harvest: Jun 14 – Aug 2

Percentages indicate frost risk at transplant. The 70% safe window means there is a 30% chance of frost after transplant — suitable for cold-hardy crops or gardeners with frost protection. The 90% safe window is best for tender plants.

Plant Water Budget

Plant needs
0.5″/week
Rainfall provides
0.7″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft
Drought risk

Water stress score is 6/10 โ€” consider drought-tolerant varieties and mulching

Sunflower needs ~1,870 GDD — county provides 5,940 GDD Excellent fit

Sunflower Planting Timeline โ€” Terrell County, TX

Sunflower Planting Calendar

Activity When Date Range
Start Indoors January 12 Jan 12 โ€“ Jan 26
Transplant Outdoors March 16 Mar 16 โ€“ Mar 30
Direct Sow March 9 Mar 9 โ€“ Mar 30
Harvest May 25 May 25 โ€“ Jul 13

Plant 1" deep ยท 18" apart ยท Rows 30" apart

Month-by-Month Timeline

MonthActivities
January Start Indoors
February โ€”
March Transplant Outdoors Direct Sow
April โ€”
May Harvest
June Harvest
July Harvest
August โ€”
September โ€”
October โ€”
November โ€”
December โ€”

Growing Conditions

Sun

Full Sun (6-8+ hours)

Water

Low โ€” drought tolerant

Days to Maturity

70โ€“100 days

Soil pH

6 โ€“ 7.5

USDA Zone

Zone 7b

Growing Season

270 days

Growing Tips for Terrell County

Direct sow after last frost. Stake tall varieties in windy areas. Harvest seed heads when the back turns brown and seeds are plump. Dry heads upside down.

Companion Planting

Good Companions

Avoid Planting Near

  • Potatoes

Level Up Your Garden

Frequently Asked Questions

When should I plant Sunflower in Terrell County, TX?

Terrell County is in Zone 7b with an average last frost of March 2. Plan your Sunflower planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Terrell County, TX?

Terrell County, Texas is in USDA Hardiness Zone 7b. The average last spring frost is March 2 and first fall frost is November 27.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Terrell County gardeners in Zone 7b organize planting dates, track what's growing, and never miss a planting window.

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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 Terrell County, TX. Local conditions may vary. Last updated: April 2026.