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When to Plant Watermelon in Jackson County, MS

Jackson County, Mississippi Zone 9a May

Your May gardening checklist

If you only do a handful of things in the garden this May, make it these. They're sequenced around your zone's frost timing.

Avg. last frost March 2
Avg. first frost November 26
Soil temp (4") 74°F
Watering Low
Pest pressure High
Daylight 13.5 hrs
  1. Bring in the watermelon

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

A few tasks this May that'll pay off in 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.

Jackson County, Mississippi is in USDA Zone 9a. The average last spring frost is March 2 and the first fall frost is November 26, giving you a growing season of approximately 269 days.

At an elevation of 182 feet, Jackson County receives approximately 57.7 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 91°F, providing good warmth for Watermelon during the growing season. Sandy soil warms quickly in spring — great for early planting — but Watermelon will need more frequent watering and organic matter to retain nutrients. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Watermelon root diseases.

Jackson County, MS (Zone 9a) Long season
269 days
Last Spring Frost March 2
269 growing days
First Fall Frost November 26
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Jackson County Soil Profile

Soil Type

Sandy Loam

Soil pH

5.1-6.1

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (151 days to spare)
Start indoors: Jan 17 Transplant: Feb 21 🍅 Harvest: May 2 – Jun 20
Recommended (50%) ✓ Fits season (143 days to spare)
Start indoors: Feb 2 Transplant: Mar 9 🍅 Harvest: May 18 – Jul 6
Safe Start (90%) ✓ Fits season (141 days to spare)
Start indoors: Feb 25 Transplant: Apr 1 🍅 Harvest: Jun 10 – Jul 29

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 Jackson County

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

Soil pH

Your soil pH (5.1–6.1) is more acidic than Watermelon prefers (6.0–7.5). Add garden lime to raise pH.

Soil Texture

Sandy soil in Jackson County warms quickly in spring but drains fast. Watermelon will need more frequent watering and regular compost additions to retain nutrients.

Drainage

Drainage is adequate for Watermelon.

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 269-day season

Sow every 8 weeks. Last sowing by Aug 18 to harvest before frost.

Plant Water Budget

Plant needs
1.5″/week
Rainfall provides
0.9″/week
You supply
0.2″/week
Watering frequency Only during dry spells
Season total 357 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 5.3" 0" ❄️ Dormant
Feb 4.5" 0" ❄️ Dormant
Mar 6.5" 5.1" 1.4" 💧 Light watering
Apr 6.5" 4.5" 2" 💧 Light watering
May 6.5" 5.1" 1.4" 💧 Light watering
Jun 6.5" 4.7" 1.8" 💧 Light watering
Jul 6.5" 6.2" 0.3" 💧 Light watering
Aug 6.5" 4.8" 1.7" 💧 Light watering
Sep 6.5" 4.9" 1.6" 💧 Light watering
Oct 6.5" 3.8" 2.7" 💧 Light watering
Nov 6.5" 4.4" 2.1" 💧 Light watering
Dec 4.4" 0" ❄️ Dormant

Water needs are for active growing months only (Mar–Nov in Jackson 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 4,909 GDD Excellent fit

Watermelon Planting Timeline — Jackson County, MS

Watermelon Planting Calendar

Activity When Date Range
Start Indoors February 2 Feb 2 – Feb 16
Transplant Outdoors March 9 Mar 9 – Mar 23
Direct Sow March 2 Mar 2 – Mar 23
Harvest May 18 May 18 – Jul 6

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
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Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

1.5"/week · Only during dry spells

📅 Days to Maturity

70–100 days

🧪 Soil pH

Needs 6–7.5 · Your soil: too_acidic

🗺️ USDA Zone

Zone 9a

📆 Growing Season

269 days in Jackson County

Growing Tips for Watermelon in Jackson County

Direct sow Watermelon outdoors after March 02 in Jackson County when soil has warmed and frost danger has passed.

Sandy soil in Jackson County dries quickly — mulch Watermelon with 2-3 inches of straw and water deeply 2-3 times per week rather than lightly every day.

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 Jackson 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 Jackson County, MS?

Jackson County is in Zone 9a with an average last frost of March 2. Plan your Watermelon planting based on this frost date — see the calendar above for exact timing.

What planting zone is Jackson County, MS?

Jackson County, Mississippi is in USDA Hardiness Zone 9a. The average last spring frost is March 2 and first fall frost is November 26.

🌱

Your Jackson County Garden Planner — Free

A 24-page printable planner built for Jackson County (Zone 9a). 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 Jackson 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.