Blog

When to plant Watermelon in Phillips County, KS

For Phillips County, gardeners: plant Watermelon May 6 through May 27 once soil reads 50°F.

When to Plant Watermelon in Phillips County, KS

Watermelon
Phillips County, Kansas Zone 6a June

This month in Phillips County, Kansas

Each item below is timed to Phillips County, Kansas's frost dates and soil temperatures. Skip nothing, stress about nothing.

Avg. last frost April 29
Avg. first frost October 10
Soil temp (4") 70°F
Watering Low
Pest pressure High
Daylight 14.8 hrs
  1. Fire up the seed-starting tray: watermelon

    Starting these indoors now means sturdy transplants ready the moment your soil warms up.

A few tasks this June that'll pay off in July
  • First harvests: watermelon

Instant PDF download. No spam, unsubscribe any time.

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.

Phillips County, Kansas is in USDA Zone 6a. The average last spring frost is April 29 and the first fall frost is October 10, giving you a growing season of approximately 164 days.

At an elevation of 929 feet, Phillips County receives approximately 32.1 inches of rainfall annually with predominantly loam soil. Summer highs average 84°F, so choose short-season varieties of Watermelon to ensure they mature before fall.

Phillips County, KS (Zone 6a) Moderate season
164 days
Last Spring Frost April 29
164 growing days
First Fall Frost October 10

Phillips County Soil Profile

Soil Type

Loam

Soil pH

6.7-7.5

Drainage

Well Drained

Watermelon Planting Risk Windows

Early Start (70% safe) ✓ Fits season (34 days to spare)
Start indoors: Mar 18 Transplant: May 6 🍅 Harvest: Jul 15 – Sep 2
Recommended (50%) ✓ Fits season (31 days to spare)
Start indoors: Mar 25 Transplant: May 13 🍅 Harvest: Jul 22 – Sep 9
Safe Start (90%) ✓ Fits season (32 days to spare)
Start indoors: Apr 8 Transplant: May 27 🍅 Harvest: Aug 5 – Sep 23

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 Phillips County

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

Soil pH

Your soil pH (6.7–7.5) is within Watermelon's preferred range (6.0–7.5).

Soil Texture

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

Organic Matter

Organic matter is excellent (4.3%) — Watermelon will thrive.

How to Plant Watermelon

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

Succession Planting Watermelon

2
successive plantings in your 164-day season

Sow every 8 weeks. Last sowing by Jul 02 to harvest before frost.

Watermelon Water Budget

Plant needs
1.5″/week
Rainfall provides
0.8″/week
You supply
0.8″/week
Watering frequency 2-3 times/week
Season total 1,187 gal / 100 sq ft
Drought risk

Water stress score is 8/10 — 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 0.9" 0" ❄️ Dormant
Feb 1.2" 0" ❄️ Dormant
Mar 2.2" 0" ❄️ Dormant
Apr 6.5" 3.8" 2.7" 💧 Light watering
May 6.5" 5.1" 1.4" 💧 Light watering
Jun 6.5" 5.4" 1.1" 💧 Light watering
Jul 6.5" 3.8" 2.7" 💧 Light watering
Aug 6.5" 3.2" 3.3" 🚿 Regular watering
Sep 6.5" 3" 3.5" 🚿 Regular watering
Oct 6.5" 1.7" 4.8" 🚿 Regular watering
Nov 1.1" 0" ❄️ Dormant
Dec 0.8" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Phillips 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 ~1,105 GDD — county provides 2,132 GDD Excellent fit

Watermelon Planting Timeline — Phillips County, KS

Watermelon Planting Calendar

Activity When Date Range
Start Indoors March 25 Mar 25 – Apr 8
Transplant Outdoors May 13 May 13 – May 27
Direct Sow May 6 May 6 – May 27
Harvest July 22 Jul 22 – Sep 9

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

Month-by-Month Timeline

MonthActivities
January
February
March Start Indoors
April Start Indoors
May Transplant Outdoors Direct Sow
June
July Harvest
August Harvest
September Harvest
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 6a

📆 Growing Season

164 days in Phillips County

Growing Tips for Watermelon in Phillips County

Direct sow Watermelon outdoors after April 29 in Phillips 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 Phillips County, KS?

Phillips County is in Zone 6a with an average last frost of April 29. Plan your Watermelon planting based on this frost date — see the calendar above for exact timing.

What planting zone is Phillips County, KS?

Phillips County, Kansas is in USDA Hardiness Zone 6a. The average last spring frost is April 29 and first fall frost is October 10.

When should I plant Watermelon in Phillips County, KS?

In Phillips County, KS, plant Watermelon after the last frost (around April 29) and before the first frost (around October 10). Best results when soil holds above 50°F.

What growing zone is Phillips County, KS for Watermelon?

Phillips County sits in USDA Zone 6a. Watermelon grows reliably in zones 4a through 11b, so it's a good fit here.

Can Watermelon grow in Phillips County's climate?

Yes — Watermelon grows well in Phillips County's temperate climate. Phillips County averages a 164-day frost-free season, with last frost around April 29 and first frost around October 10.

🌱

Your Phillips County Garden Planner — Free

A 22-page printable planner built for Phillips County (Zone 6a). 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 Phillips County, KS. Local conditions may vary. Last updated: June 2026.

Sources & credits

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