Blog

When to Plant Watermelon in Dade County, MO

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.

Dade County, Missouri is in USDA Zone 6a. The average last spring frost is April 8 and the first fall frost is October 26, giving you a growing season of approximately 201 days.

At an elevation of 660 feet, Dade County receives approximately 37.8 inches of rainfall annually with predominantly silt loam soil. Summer highs average 85ยฐF, providing good warmth for Watermelon during the growing season.

Dade County, MO (Zone 6a) Long season
201 days
Last Spring Frost April 8
201 growing days
First Fall Frost October 26

Dade County Soil Profile

Soil Type

Silt Loam

Soil pH

5.6-6.8

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (68 days to spare)
Start indoors: Feb 25 Transplant: Apr 15 🍅 Harvest: Jun 24 – Aug 12
Recommended (50%) ✓ Fits season (68 days to spare)
Start indoors: Mar 4 Transplant: Apr 22 🍅 Harvest: Jul 1 – Aug 19
Safe Start (90%) ✓ Fits season (71 days to spare)
Start indoors: Mar 15 Transplant: May 3 🍅 Harvest: Jul 12 – Aug 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 Dade County

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

Soil pH

Your soil pH (5.6โ€“6.8) overlaps with Watermelon's range (6.0โ€“7.5), though not a perfect match.

Soil Texture

The silt loam soil in Dade County is excellent for Watermelon โ€” good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

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

How to Plant Watermelon

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

Succession Planting Watermelon

3
successive plantings in your 201-day season

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

Plant Water Budget

Plant needs
1.5″/week
Rainfall provides
0.8″/week
You supply
0.9″/week
Watering frequency 2-3 times/week
Season total 1,524 gal / 100 sq ft
Drought risk

Water stress score is 6/10 โ€” consider drought-tolerant varieties and mulching

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 โ€” 1.7" 0" โ„๏ธ Dormant
Feb โ€” 1.7" 0" โ„๏ธ Dormant
Mar โ€” 2.4" 0" โ„๏ธ Dormant
Apr 6.5" 3.5" 3" ๐Ÿ’ง Light watering
May 6.5" 4.9" 1.6" ๐Ÿ’ง Light watering
Jun 6.5" 4.3" 2.2" ๐Ÿ’ง Light watering
Jul 6.5" 3.7" 2.8" ๐Ÿ’ง Light watering
Aug 6.5" 4.4" 2.1" ๐Ÿ’ง Light watering
Sep 6.5" 3.4" 3.1" ๐Ÿ’ง Light watering
Oct 6.5" 3.1" 3.4" ๐Ÿšฟ Regular watering
Nov โ€” 2.6" 0" โ„๏ธ Dormant
Dec โ€” 2.2" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Aprโ€“Oct in Dade County). Supplement amounts are based on average rainfall โ€” 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" โ€” every day above 50ยฐF 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 ~1,169 GDD — county provides 2,763 GDD Excellent fit

Watermelon Planting Timeline โ€” Dade County, MO

Watermelon Planting Calendar

Activity When Date Range
Start Indoors March 4 Mar 4 โ€“ Mar 18
Transplant Outdoors April 22 Apr 22 โ€“ May 6
Direct Sow April 15 Apr 15 โ€“ May 6
Harvest July 1 Jul 1 โ€“ Aug 19

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

Month-by-Month Timeline

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

Growing Conditions

โ˜€๏ธ Sun

Full Sun (6-8+ hours)

๐Ÿ’ง Water

1.5"/week ยท 2-3 times/week

๐Ÿ“… Days to Maturity

70โ€“100 days

๐Ÿงช Soil pH

Needs 6โ€“7.5 ยท Your soil: acceptable

๐Ÿ—บ๏ธ USDA Zone

Zone 6a

๐Ÿ“† Growing Season

201 days in Dade County

Growing Tips for Watermelon in Dade County

Direct sow Watermelon outdoors after April 08 in Dade County when soil has warmed and frost danger has passed.

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.

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 Dade County, MO?

Dade County is in Zone 6a with an average last frost of April 8. Plan your Watermelon planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Dade County, MO?

Dade County, Missouri is in USDA Hardiness Zone 6a. The average last spring frost is April 8 and first fall frost is October 26.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Dade County gardeners in Zone 6a organize planting dates, track what's growing, and never miss a planting window.

Get Your Free Garden Planner →

Free download. Plan your entire garden season in minutes.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Dade County, MO. Local conditions may vary. Last updated: April 2026.