Blog

When to Plant Sunflower in Freestone County, TX

Freestone County, Texas Zone 8b June

Freestone County, Texas gardeners: here's your June plan

Welcome to June in Zone 8b. These are the moves that will have the biggest impact on your growing season.

Avg. last frost March 11
Avg. first frost November 13
Soil temp (4") 81°F
Watering Low
Pest pressure High
Daylight 14.1 hrs
  1. Pick sunflower

    Check every 1–2 days. Many of these get tough or go to seed if you wait too long.

Before July arrives, get these ready
  • First harvests: sunflower

Instant PDF download. No spam, unsubscribe any time.

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.

Freestone County, Texas is in USDA Zone 8b. The average last spring frost is March 11 and the first fall frost is November 13, giving you a growing season of approximately 247 days.

At an elevation of 398 feet, Freestone County receives approximately 71.4 inches of rainfall annually with predominantly clay soil. Summer highs average 93°F, providing good warmth for Sunflower during the growing season. Clay soil retains moisture well for Sunflower, but amend with compost to improve drainage and prevent root rot. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Sunflower root diseases.

Annual Blooms in Summer Pollinator-friendly Good for cutting
Freestone County, TX (Zone 8b) Long season
247 days
Last Spring Frost March 11
247 growing days
First Fall Frost November 13

Freestone County Soil Profile

Soil Type

Clay

Soil pH

6.9-7.9

Drainage

Well Drained

Sunflower Planting Risk Windows

Early Start (70% safe) ✓ Fits season (34 days to spare)
Start indoors: Feb 13 Transplant: Feb 20 🌸 Bloom: May 15 – Oct 2
Recommended (50%) ✓ Fits season (37 days to spare)
Start indoors: Feb 18 Transplant: Feb 25 🌸 Bloom: May 20 – Oct 7
Safe Start (90%) ✓ Fits season (32 days to spare)
Start indoors: Mar 13 Transplant: Mar 20 🌸 Bloom: Jun 12 – Oct 30

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 Freestone County

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

Soil pH

Your soil pH (6.9–7.9) overlaps with Sunflower's range (6.0–7.5), though not a perfect match.

Soil Texture

Heavy clay soil (46% clay) in Freestone County compacts easily and drains slowly. Amend with compost and avoid working soil when wet.

Organic Matter

Organic matter is moderate (3.1%). Annual compost additions will help Sunflower.

How to Plant Sunflower

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

Succession Planting Sunflower

4
successive plantings in your 247-day season

Sow every 8 weeks. Last sowing by Aug 05 to harvest before frost.

Sunflower Water Budget

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

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 1.8" 0" ❄️ Dormant
Feb 2.7" 0" ❄️ Dormant
Mar 2.2" 4.8" 0" ✅ Rainfall sufficient
Apr 2.2" 7" 0" ✅ Rainfall sufficient
May 2.2" 12.2" 0" ✅ Rainfall sufficient
Jun 2.2" 10.3" 0" ✅ Rainfall sufficient
Jul 2.2" 8.2" 0" ✅ Rainfall sufficient
Aug 2.2" 9.1" 0" ✅ Rainfall sufficient
Sep 2.2" 6.1" 0" ✅ Rainfall sufficient
Oct 2.2" 5" 0" ✅ Rainfall sufficient
Nov 2.2" 2.3" 0" ✅ Rainfall sufficient
Dec 1.9" 0" ❄️ Dormant

Water needs are for active growing months only (Mar–Nov in Freestone 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 ~1,679 GDD — county provides 4,878 GDD Excellent fit

Sunflower Planting Timeline — Freestone County, TX

Sunflower Planting Calendar

Activity When Date Range
Start Indoors February 18 Feb 18 – Mar 4
Transplant Outdoors February 25 Feb 25 – Mar 11
Direct Sow February 25 Feb 25 – Mar 18
Bloom May 20 May 20 – Oct 7

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

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

0.5"/week · Natural rainfall sufficient

📅 Days to Maturity

70–100 days

🧪 Soil pH

Needs 6–7.5 · Your soil: acceptable

🗺️ USDA Zone

Zone 8b

📆 Growing Season

247 days in Freestone County

Growing Tips for Sunflower in Freestone County

Direct sow Sunflower outdoors after March 11 in Freestone County when soil has warmed and frost danger has passed.

With Freestone County's clay soil (46% clay), work in 3-4 inches of compost before planting Sunflower. Avoid tilling when soil is wet to prevent compaction.

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

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 Freestone County, TX?

Freestone County is in Zone 8b with an average last frost of March 11. Plan your Sunflower planting based on this frost date — see the calendar above for exact timing.

What planting zone is Freestone County, TX?

Freestone County, Texas is in USDA Hardiness Zone 8b. The average last spring frost is March 11 and first fall frost is November 13.

🌱

Your Freestone County Garden Planner — Free

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

Instant PDF download. No spam, unsubscribe any time.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Freestone 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.