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When to Plant Sunflower in Texas County, OK

Texas County, Oklahoma Zone 6b June

Your June game plan for Texas County, Oklahoma

Your garden in Texas County, Oklahoma is working on a schedule, even when you're not. Here's where you should be this June.

Avg. last frost April 16
Avg. first frost October 20
Soil temp (4") 75°F
Watering Moderate
Pest pressure High
Daylight 14.5 hrs
To set up a strong July, finish these tasks
  • First harvests: sunflower

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Sunflower (Helianthus annuus) is a fast-growing North American native annual famous for its towering stems and brilliant yellow heads. It thrives in full sun and heat, producing large, pollen-rich blooms that attract bees, butterflies, and seed-eating birds. Varieties range from 18-inch dwarfs to 12-foot giants and nearly every color except blue.

Texas County, Oklahoma is in USDA Zone 6b. The average last spring frost is April 16 and the first fall frost is October 20, giving you a growing season of approximately 187 days.

At an elevation of 870 feet, Texas County receives approximately 20.3 inches of rainfall annually with predominantly loam soil. Summer highs average 89°F, providing good warmth for Sunflower during the growing season.

Annual Blooms in Summer Pollinator-friendly Good for cutting
Texas County, OK (Zone 6b) Moderate season
187 days
Last Spring Frost April 16
187 growing days
First Fall Frost October 20
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Texas County Soil Profile

Soil Type

Loam

Soil pH

6.5-7.8

Drainage

Well Drained

Sunflower Planting Risk Windows

Early Start (70% safe) ✓ Fits season (11 days to spare)
Start indoors: Mar 22 Transplant: Apr 12 🌸 Bloom: Jul 5 – Oct 4
Recommended (50%) ✓ Fits season (12 days to spare)
Start indoors: Mar 26 Transplant: Apr 16 🌸 Bloom: Jul 9 – Oct 8
Safe Start (90%) ✓ Fits season (11 days to spare)
Start indoors: Apr 11 Transplant: May 2 🌸 Bloom: Jul 25 – Oct 24

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.

Soil Compatibility in Texas County

How your county's soil matches Sunflower's growing requirements.

Soil pH

Your soil pH (6.5–7.8) overlaps with Sunflower's range (6.0–7.5), though not a perfect match.

Soil Texture

The loam soil in Texas County is excellent for Sunflower — good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is excellent (4.1%) — Sunflower will thrive.

How to Plant Sunflower

1"
Planting Depth
18"
Between Plants
24"
Between Rows

Succession Planting Sunflower

3
successive plantings in your 187-day season

Sow every 8 weeks. Last sowing by Jul 12 to harvest before frost.

Sunflower Water Budget

Plant needs
0.5″/week
Rainfall provides
0.5″/week
You supply
0.1″/week
Watering frequency Only during dry spells
Season total 88 gal / 100 sq ft
Drought risk

Water stress score is 10/10 — consider drought-tolerant varieties and mulching

Monthly Watering Guide for Sunflower

Sunflower needs approximately 0.5 inches of water per week (2.2" per month). Here's how your county's rainfall compares month by month.

Month Sunflower Needs Rainfall You Supplement Action
Jan 0.5" 0" ❄️ Dormant
Feb 0.7" 0" ❄️ Dormant
Mar 1.4" 0" ❄️ Dormant
Apr 2.2" 2.1" 0.1" 💧 Light watering
May 2.2" 3" 0" ✅ Rainfall sufficient
Jun 2.2" 3.4" 0" ✅ Rainfall sufficient
Jul 2.2" 2.3" 0" ✅ Rainfall sufficient
Aug 2.2" 2.3" 0" ✅ Rainfall sufficient
Sep 2.2" 2.1" 0.1" 💧 Light watering
Oct 2.2" 1.4" 0.8" 💧 Light watering
Nov 0.7" 0" ❄️ Dormant
Dec 0.5" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Texas County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.

Sunflower Heat Requirements (GDD)

What are Growing Degree Days (GDD)?

Growing Degree Days measure the total warmth your plants receive during the growing season. Think of it as a "heat bank" — every day above 50°F deposits warmth that helps your plants grow.

Each plant needs a certain amount of accumulated heat to mature. If your county provides more GDD than the plant needs, it's a great fit. If it's close, you may want to choose faster-maturing varieties or start seeds indoors to get a head start.

Sunflower needs ~1,424 GDD — county provides 3,132 GDD Excellent fit

Sunflower Planting Timeline — Texas County, OK

Sunflower Planting Calendar

Activity When Date Range
Start Indoors March 26 Mar 26 – Apr 9
Transplant Outdoors April 16 Apr 16 – Apr 30
Direct Sow April 16 Apr 16 – May 7
Bloom July 9 Jul 9 – Oct 8

Plant 1" deep · 18" apart · Rows 24" apart

Month-by-Month Timeline

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

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

0.5"/week · Only during dry spells

📅 Days to Maturity

70–100 days

🧪 Soil pH

Needs 6–7.5 · Your soil: acceptable

🗺️ USDA Zone

Zone 6b

📆 Growing Season

187 days in Texas County

Growing Tips for Sunflower in Texas County

Direct sow Sunflower outdoors after April 16 in Texas County when soil has warmed and frost danger has passed.

Common pests for Sunflower in this region include aphids and slugs. Use row covers early in the season and inspect plants weekly.

Texas County receives only 20" of rain annually. Sunflower needs consistent moisture — install drip irrigation or water deeply 2-3 times per week.

General growing tips

Direct-sow 1 inch deep after last frost; germination takes 7-14 days at 65-75°F soil. Sunflowers dislike root disturbance so direct sowing is strongly preferred over transplanting. Plant in succession every 2 weeks for extended bloom. Stake tall varieties. Avoid overwatering — they tolerate drought once established. Birds will self-deadhead seed heads; leave them up through fall for wildlife.

Companion Planting

Good Companions

Avoid Planting Near

  • Potatoes
  • Pole_beans

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Sunflower in Texas County, OK?

Texas County is in Zone 6b with an average last frost of April 16. Plan your Sunflower planting based on this frost date — see the calendar above for exact timing.

What planting zone is Texas County, OK?

Texas County, Oklahoma is in USDA Hardiness Zone 6b. The average last spring frost is April 16 and first fall frost is October 20.

🌱

Your Texas County Garden Planner — Free

A 22-page printable planner built for Texas County (Zone 6b). 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 Texas County, OK. Local conditions may vary. Last updated: June 2026.

Sources & credits

Every number on this page traces back to a primary horticulture or government data source. Click through to verify.