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When to Plant Sunflower in Parmer County, TX

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.

Parmer County, Texas is in USDA Zone 7a. The average last spring frost is April 16 and the first fall frost is October 23, giving you a growing season of approximately 190 days.

At an elevation of 1,686 feet, Parmer County receives approximately 53.4 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 95°F, so Sunflower may need afternoon shade and extra watering during peak heat. Sandy soil warms quickly in spring — great for early planting — but Sunflower will need more frequent watering and organic matter to retain nutrients. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Sunflower root diseases.

Annual Blooms in Summer Pollinator-friendly Good for cutting
Parmer County, TX (Zone 7a) Moderate season
190 days
Last Spring Frost April 16
190 growing days
First Fall Frost October 23

Parmer County Soil Profile

Soil Type

Sandy Loam

Soil pH

7.3-8.5

Drainage

Well Drained

Monthly Watering Guide for Sunflower

Sunflower needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.

Month Sunflower Needs Rainfall You Supplement Action
Jan 3.4" 0" ❄️ Dormant
Feb 3" 0" ❄️ Dormant
Mar 3" 0" ❄️ Dormant
Apr 4.3" 1.8" 2.5" 🚿 Regular watering
May 4.3" 1.2" 3.1" 🚿 Regular watering
Jun 4.3" 1.8" 2.5" 🚿 Regular watering
Jul 4.3" 9.7" 0" ✅ Rainfall sufficient
Aug 4.3" 10.8" 0" ✅ Rainfall sufficient
Sep 4.3" 7.4" 0" ✅ Rainfall sufficient
Oct 4.3" 5.2" 0" ✅ Rainfall sufficient
Nov 2.8" 0" ❄️ Dormant
Dec 3.2" 0" ❄️ Dormant

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

Sunflower Planting Timeline — Parmer County, TX

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 15

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

Low — drought tolerant

📅 Days to Maturity

70–100 days

🧪 Soil pH

Needs 6–7.5 · Your soil: N/A

🗺️ USDA Zone

Zone 7a

📆 Growing Season

190 days in Parmer County

Growing Tips for Parmer County

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 Parmer County, TX?

Parmer County is in Zone 7a 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 Parmer County, TX?

Parmer County, Texas is in USDA Hardiness Zone 7a. The average last spring frost is April 16 and first fall frost is October 23.

🌱

Your Parmer County Garden Planner — Free

A 22-page printable planner built for Parmer County (Zone 7a). 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 Parmer County, TX. 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.