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When to Plant Watermelon in Vernon Parish, LA

Vernon Parish, Louisiana Zone 9a May

This month in Vernon Parish, Louisiana

Your garden in Vernon Parish, Louisiana is working on a schedule, even when you're not. Here's where you should be this May.

Avg. last frost March 5
Avg. first frost November 16
Soil temp (4") 72°F
Watering Moderate
Pest pressure High
Daylight 13.6 hrs
  1. Bring in the watermelon

    The more you pick, the more the plant produces. Letting fruit overripen tells the plant it's time to stop.

Before June arrives, get these ready
  • First harvests: watermelon

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Watermelon is a sprawling vine crop that produces sweet, juicy fruits in hot weather. Varieties range from personal-sized icebox types to 50-pound giants.

Vernon Parish, Louisiana is in USDA Zone 9a. The average last spring frost is March 5 and the first fall frost is November 16, giving you a growing season of approximately 256 days.

At an elevation of 481 feet, Vernon Parish receives approximately 54.2 inches of rainfall annually with predominantly loam soil. Summer highs average 97°F, so Watermelon may need afternoon shade and extra watering during peak heat. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Watermelon root diseases.

Vernon Parish, LA (Zone 9a) Long season
256 days
Last Spring Frost March 5
256 growing days
First Fall Frost November 16

Vernon Parish Soil Profile

Soil Type

Loam

Soil pH

6.1-7.2

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (136 days to spare)
Start indoors: Jan 25 Transplant: Mar 1 🍅 Harvest: May 10 – Jun 28
Recommended (50%) ✓ Fits season (130 days to spare)
Start indoors: Feb 5 Transplant: Mar 12 🍅 Harvest: May 21 – Jul 9
Safe Start (90%) ✓ Fits season (126 days to spare)
Start indoors: Mar 9 Transplant: Apr 13 🍅 Harvest: Jun 22 – Aug 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 Vernon Parish

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

Soil pH

Your soil pH (6.1–7.2) is within Watermelon's preferred range (6.0–7.5).

Soil Texture

The loam soil in Vernon Parish is excellent for Watermelon — good drainage, moisture retention, and nutrient holding capacity.

Drainage

Drainage is adequate for Watermelon.

Organic Matter

Organic matter is moderate (2.5%). Annual compost additions will help Watermelon.

How to Plant Watermelon

1"
Planting Depth
30"
Between Plants
42"
Between Rows

Succession Planting Watermelon

4
successive plantings in your 256-day season

Sow every 8 weeks. Last sowing by Aug 08 to harvest before frost.

Plant Water Budget

Plant needs
1.5″/week
Rainfall provides
0.9″/week
You supply
1.1″/week
Watering frequency 2-3 times/week
Season total 2,417 gal / 100 sq ft

Monthly Watering Guide for Watermelon

Watermelon needs approximately 1.5 inches of water per week (6.5" per month). Here's how your county's rainfall compares month by month.

Month Watermelon Needs Rainfall You Supplement Action
Jan 4.6" 0" ❄️ Dormant
Feb 4.7" 0" ❄️ Dormant
Mar 6.5" 5.4" 1.1" 💧 Light watering
Apr 6.5" 3.4" 3.1" 💧 Light watering
May 6.5" 3.7" 2.8" 💧 Light watering
Jun 6.5" 4.7" 1.8" 💧 Light watering
Jul 6.5" 5.8" 0.7" 💧 Light watering
Aug 6.5" 5.1" 1.4" 💧 Light watering
Sep 6.5" 4.1" 2.4" 💧 Light watering
Oct 6.5" 3.8" 2.7" 💧 Light watering
Nov 6.5" 4.3" 2.2" 💧 Light watering
Dec 4.6" 0" ❄️ Dormant

Water needs are for active growing months only (Mar–Nov in Vernon Parish). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.

Watermelon 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.

Watermelon needs ~1,934 GDD — county provides 5,824 GDD Excellent fit

Watermelon Planting Timeline — Vernon Parish, LA

Watermelon Planting Calendar

Activity When Date Range
Start Indoors February 5 Feb 5 – Feb 19
Transplant Outdoors March 12 Mar 12 – Mar 26
Direct Sow March 5 Mar 5 – Mar 26
Harvest May 21 May 21 – Jul 9

Plant 1" deep · 30" apart · Rows 42" apart

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

1.5"/week · 2-3 times/week

📅 Days to Maturity

70–100 days

🧪 Soil pH

Needs 6–7.5 · Your soil: ideal

🗺️ USDA Zone

Zone 9a

📆 Growing Season

256 days in Vernon Parish

Growing Tips for Watermelon in Vernon Parish

Direct sow Watermelon outdoors after March 05 in Vernon Parish when soil has warmed and frost danger has passed.

With summer highs reaching 97°F in Vernon Parish, provide afternoon shade for Watermelon and water deeply in the morning.

Common pests for Watermelon in this region include squash vine borer and cucumber beetles. Use row covers early in the season and inspect plants weekly.

General growing tips

Start seeds indoors 3-4 weeks early or direct sow after soil is warm. Plant on mounds with plenty of space. Check ripeness by looking for a yellow ground spot and dull thump when tapped.

Recommended Watermelon Varieties for Vernon Parish

Full-size melons that thrive with your long season

Crimson Sweet (85d) Charleston Gray (85d) Moon and Stars (95d)

Companion Planting

Good Companions

Avoid Planting Near

  • Potatoes

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Watermelon in Vernon Parish, LA?

Vernon Parish is in Zone 9a with an average last frost of March 5. Plan your Watermelon planting based on this frost date — see the calendar above for exact timing.

What planting zone is Vernon Parish, LA?

Vernon Parish, Louisiana is in USDA Hardiness Zone 9a. The average last spring frost is March 5 and first fall frost is November 16.

🌱

Your Vernon Parish Garden Planner — Free

A 24-page printable planner built for Vernon Parish (Zone 9a). 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 Vernon Parish, LA. 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.