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When to Plant Sunflower in Kenedy County, TX

Kenedy County, Texas Zone 9b May

Your May planting checklist for Kenedy County, Texas

May is a pivotal month for Kenedy County, Texas gardens. Focus on these tasks first and you'll set up the rest of the season for success.

Avg. last frost February 13
Avg. first frost December 13
Soil temp (4") 74°F
Watering Low
Pest pressure High
Daylight 13.3 hrs
  1. Pick sunflower

    Morning harvests are best — cooler temperatures mean crisper produce and longer fridge life.

Coming up in June — start thinking about
  • First harvests: sunflower

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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.

Kenedy County, Texas is in USDA Zone 9b. The average last spring frost is February 13 and the first fall frost is December 13, giving you a growing season of approximately 303 days.

At an elevation of 1,757 feet, Kenedy County receives approximately 58.7 inches of rainfall annually with predominantly loam soil. Summer highs average 101°F, so Sunflower may need afternoon shade and extra watering during peak heat. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Sunflower root diseases.

Kenedy County, TX (Zone 9b) Year-round
303 days
Last Spring Frost February 13
303 growing days
First Fall Frost December 13

Kenedy County Soil Profile

Soil Type

Loam

Soil pH

6.6-7.5

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (195 days to spare)
Start indoors: Dec 7 Transplant: Jan 25 🍅 Harvest: Apr 5 – May 24
Recommended (50%) ✓ Fits season (177 days to spare)
Start indoors: Jan 2 Transplant: Feb 20 🍅 Harvest: May 1 – Jun 19
Safe Start (90%) ✓ Fits season (167 days to spare)
Start indoors: Jan 23 Transplant: Mar 13 🍅 Harvest: May 22 – Jul 10

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 Kenedy County

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

Soil pH

Your soil pH (6.6–7.5) is within Sunflower's preferred range (6.0–7.5).

Soil Texture

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

Organic Matter

Organic matter is moderate (2.2%). Annual compost additions will help Sunflower.

How to Plant Sunflower

1"
Planting Depth
18"
Between Plants
30"
Between Rows

Succession Planting Sunflower

5
successive plantings in your 303-day season

Sow every 8 weeks. Last sowing by Sep 04 to harvest before frost.

Plant Water Budget

Plant needs
0.5″/week
Rainfall provides
0.8″/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 1.5" 0" ❄️ Dormant
Feb 2.2" 2" 0.2" 💧 Light watering
Mar 2.2" 3.9" 0" ✅ Rainfall sufficient
Apr 2.2" 6" 0" ✅ Rainfall sufficient
May 2.2" 8.2" 0" ✅ Rainfall sufficient
Jun 2.2" 9.2" 0" ✅ Rainfall sufficient
Jul 2.2" 8" 0" ✅ Rainfall sufficient
Aug 2.2" 7.8" 0" ✅ Rainfall sufficient
Sep 2.2" 5.6" 0" ✅ Rainfall sufficient
Oct 2.2" 3.2" 0" ✅ Rainfall sufficient
Nov 2.2" 1.9" 0.3" 💧 Light watering
Dec 2.2" 1.4" 0.8" 💧 Light watering

Water needs are for active growing months only (Feb–Dec in Kenedy 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 ~2,189 GDD — county provides 7,828 GDD Excellent fit

Sunflower Planting Timeline — Kenedy County, TX

Sunflower Planting Calendar

Activity When Date Range
Start Indoors January 2 Jan 2 – Jan 16
Transplant Outdoors February 20 Feb 20 – Mar 6
Direct Sow February 13 Feb 13 – Mar 6
Harvest May 1 May 1 – Jun 19

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

Month-by-Month Timeline

MonthActivities
January Start Indoors
February Transplant Outdoors Direct Sow
March Transplant Outdoors Direct Sow
April
May Harvest
June Harvest
July
August
September
October
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: ideal

🗺️ USDA Zone

Zone 9b

📆 Growing Season

303 days in Kenedy County

Growing Tips for Sunflower in Kenedy County

Direct sow Sunflower outdoors after February 13 in Kenedy County when soil has warmed and frost danger has passed.

With summer highs reaching 101°F in Kenedy County, provide afternoon shade for Sunflower and water deeply in the morning.

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 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

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Sunflower in Kenedy County, TX?

Kenedy County is in Zone 9b with an average last frost of February 13. Plan your Sunflower planting based on this frost date — see the calendar above for exact timing.

What planting zone is Kenedy County, TX?

Kenedy County, Texas is in USDA Hardiness Zone 9b. The average last spring frost is February 13 and first fall frost is December 13.

🌱

Your Kenedy County Garden Planner — Free

A 24-page printable planner built for Kenedy County (Zone 9b). 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 Kenedy County, TX. Local conditions may vary. Last updated: May 2026.

Sources & credits

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