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When to Plant Winter Melon in Cass County, MI

Cass County, Michigan Zone 6a May

May in the garden — Cass County, Michigan

We've pulled the most time-sensitive tasks for Cass County, Michigan this May and put them front and centre. Tackle them in order.

Avg. last frost April 29
Avg. first frost October 17
Soil temp (4") 63°F
Watering Low
Pest pressure Low
Daylight 14.4 hrs
  1. Transplant winter melon outside

    Bring a watering can to the bed. Each transplant gets a drink the moment it's in the ground, not ten minutes later.

  2. Put winter melon seeds straight in the ground

    Mark the row. Birds and stray feet both have opinions about unmarked beds.

Coming up in June — start thinking about
  • Starting indoors: winter melon

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Winter melon (wax gourd) is a large Asian squash with a waxy white coating that allows long storage. The mild flesh is used in soups and stir-fries.

Cass County, Michigan is in USDA Zone 6a. The average last spring frost is April 29 and the first fall frost is October 17, giving you a growing season of approximately 171 days.

At an elevation of 1,030 feet, Cass County receives approximately 34.2 inches of rainfall annually with predominantly silt loam soil. Summer highs average 86°F, providing good warmth for Winter Melon during the growing season.

Cass County, MI (Zone 6a) Moderate season
171 days
Last Spring Frost April 29
171 growing days
First Fall Frost October 17

Cass County Soil Profile

Soil Type

Silt Loam

Soil pH

6.2-7.2

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (14 days to spare)
Start indoors: Mar 1 Transplant: May 10 🍅 Harvest: Aug 9 – Sep 27
Recommended (50%) ✓ Fits season (17 days to spare)
Start indoors: Mar 4 Transplant: May 13 🍅 Harvest: Aug 12 – Sep 30
Safe Start (90%) ✓ Fits season (9 days to spare)
Start indoors: Mar 24 Transplant: Jun 2 🍅 Harvest: Sep 1 – Oct 20

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 Cass County

How your county's soil matches Winter Melon's growing requirements.

Soil pH

Your soil pH (6.2–7.2) overlaps with Winter Melon's range (6.0–7.0), though not a perfect match.

Soil Texture

The silt loam soil in Cass County is excellent for Winter Melon — good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is excellent (4.9%) — Winter Melon will thrive.

How to Plant Winter Melon

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

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
0.8″/week
You supply
0.2″/week
Watering frequency Only during dry spells
Season total 244 gal / 100 sq ft

Monthly Watering Guide for Winter Melon

Winter Melon needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.

Month Winter Melon Needs Rainfall You Supplement Action
Jan 1.5" 0" ❄️ Dormant
Feb 1.6" 0" ❄️ Dormant
Mar 2.5" 0" ❄️ Dormant
Apr 4.3" 3.5" 0.8" 💧 Light watering
May 4.3" 3.9" 0.4" 💧 Light watering
Jun 4.3" 4.5" 0" ✅ Rainfall sufficient
Jul 4.3" 3.8" 0.5" 💧 Light watering
Aug 4.3" 3.5" 0.8" 💧 Light watering
Sep 4.3" 3.2" 1.1" 💧 Light watering
Oct 4.3" 2.2" 2.1" 💧 Light watering
Nov 2.1" 0" ❄️ Dormant
Dec 1.8" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Cass County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.

Winter Melon 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.

Winter Melon needs ~1,522 GDD — county provides 2,479 GDD Excellent fit

Winter Melon Planting Timeline — Cass County, MI

Winter Melon Planting Calendar

Activity When Date Range
Start Indoors March 4 Mar 4 – Mar 18
Transplant Outdoors May 13 May 13 – May 27
Direct Sow May 6 May 6 – May 27
Harvest August 12 Aug 12 – Sep 30

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

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

1"/week · Only during dry spells

📅 Days to Maturity

90–120 days

🧪 Soil pH

Needs 6–7 · Your soil: acceptable

🗺️ USDA Zone

Zone 6a

📆 Growing Season

171 days in Cass County

Growing Tips for Winter Melon in Cass County

Direct sow Winter Melon outdoors after April 29 in Cass County when soil has warmed and frost danger has passed.

Common pests for Winter Melon 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. Provide ample space for sprawling vines. Harvest when the waxy coating develops on the rind. Fruits can weigh 15-30 pounds.

Companion Planting

Good Companions

Avoid Planting Near

  • Potatoes

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Winter Melon in Cass County, MI?

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

What planting zone is Cass County, MI?

Cass County, Michigan is in USDA Hardiness Zone 6a. The average last spring frost is April 29 and first fall frost is October 17.

🌱

Your Cass County Garden Planner — Free

A 24-page printable planner built for Cass 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.

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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 Cass County, MI. 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.