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When to Plant Watermelon in Lamar County, MS

Lamar County, Mississippi Zone 8b May

This month in Lamar County, Mississippi

Your Lamar County, Mississippi garden is entering a new phase. Here's what's on the schedule for May and why each task matters now.

Avg. last frost March 6
Avg. first frost November 21
Soil temp (4") 71°F
Watering Moderate
Pest pressure High
Daylight 13.6 hrs
  1. Start harvesting watermelon

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

Get ahead of June
  • 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.

Lamar County, Mississippi is in USDA Zone 8b. The average last spring frost is March 6 and the first fall frost is November 21, giving you a growing season of approximately 260 days.

At an elevation of 62 feet, Lamar County receives approximately 51.6 inches of rainfall annually with predominantly clay loam soil. Summer highs average 91°F, providing good warmth for Watermelon during the growing season. Clay soil retains moisture well for Watermelon, but amend with compost to improve drainage and prevent root rot. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Watermelon root diseases.

Lamar County, MS (Zone 8b) Long season
260 days
Last Spring Frost March 6
260 growing days
First Fall Frost November 21
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Lamar County Soil Profile

Soil Type

Clay Loam

Soil pH

5.8-6.4

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (126 days to spare)
Start indoors: Jan 31 Transplant: Mar 14 🍅 Harvest: May 23 – Jul 11
Recommended (50%) ✓ Fits season (127 days to spare)
Start indoors: Feb 6 Transplant: Mar 20 🍅 Harvest: May 29 – Jul 17
Safe Start (90%) ✓ Fits season (123 days to spare)
Start indoors: Feb 26 Transplant: Apr 9 🍅 Harvest: Jun 18 – Aug 6

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 Lamar County

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

Soil pH

Your soil pH (5.8–6.4) overlaps with Watermelon's range (6.0–7.5), though not a perfect match.

Soil Texture

The clay loam soil in Lamar County is excellent for Watermelon — good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is moderate (2.2%). 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 260-day season

Sow every 8 weeks. Last sowing by Aug 13 to harvest before frost.

Plant Water Budget

Plant needs
1.5″/week
Rainfall provides
0.8″/week
You supply
0.7″/week
Watering frequency 1-2 times/week
Season total 1,542 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 4.9" 0" ❄️ Dormant
Feb 3.7" 0" ❄️ Dormant
Mar 6.5" 4.9" 1.6" 💧 Light watering
Apr 6.5" 4.2" 2.3" 💧 Light watering
May 6.5" 3.5" 3" 💧 Light watering
Jun 6.5" 4.2" 2.3" 💧 Light watering
Jul 6.5" 6" 0.5" 💧 Light watering
Aug 6.5" 5.4" 1.1" 💧 Light watering
Sep 6.5" 4.2" 2.3" 💧 Light watering
Oct 6.5" 3.7" 2.8" 💧 Light watering
Nov 6.5" 3.4" 3.1" 💧 Light watering
Dec 3.7" 0" ❄️ Dormant

Water needs are for active growing months only (Mar–Nov in Lamar County). 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 ~1,551 GDD — county provides 4,745 GDD Excellent fit

Watermelon Planting Timeline — Lamar County, MS

Watermelon Planting Calendar

Activity When Date Range
Start Indoors February 6 Feb 6 – Feb 20
Transplant Outdoors March 20 Mar 20 – Apr 3
Direct Sow March 13 Mar 13 – Apr 3
Harvest May 29 May 29 – Jul 17

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

Month-by-Month Timeline

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

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

1.5"/week · 1-2 times/week

📅 Days to Maturity

70–100 days

🧪 Soil pH

Needs 6–7.5 · Your soil: acceptable

🗺️ USDA Zone

Zone 8b

📆 Growing Season

260 days in Lamar County

Growing Tips for Watermelon in Lamar County

Direct sow Watermelon outdoors after March 06 in Lamar County when soil has warmed and frost danger has passed.

With Lamar County's clay soil (27% clay), work in 3-4 inches of compost before planting Watermelon. Avoid tilling when soil is wet to prevent compaction.

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 Lamar County

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 Lamar County, MS?

Lamar County is in Zone 8b with an average last frost of March 6. Plan your Watermelon planting based on this frost date — see the calendar above for exact timing.

What planting zone is Lamar County, MS?

Lamar County, Mississippi is in USDA Hardiness Zone 8b. The average last spring frost is March 6 and first fall frost is November 21.

🌱

Your Lamar County Garden Planner — Free

A 24-page printable planner built for Lamar 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.

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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 Lamar County, MS. 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.