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When to Plant Hubbard Squash in Charlevoix County, MI

Hubbard squash is a large, bumpy-skinned winter squash with dense, sweet, dry flesh ideal for baking and pies. The hard shell allows storage for 6 months or more.

Charlevoix County, Michigan is in USDA Zone 5a. The average last spring frost is May 5 and the first fall frost is October 21, giving you a growing season of approximately 169 days.

At an elevation of 821 feet, Charlevoix County receives approximately 41.9 inches of rainfall annually with predominantly silt loam soil. Summer highs average 84ยฐF, so choose short-season varieties of Hubbard Squash to ensure they mature before fall.

Charlevoix County, MI (Zone 5a) Moderate season
169 days
Last Spring Frost May 5
169 growing days
First Fall Frost October 21

Charlevoix County Soil Profile

Soil Type

Silt Loam

Soil pH

6-6.8

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (10 days to spare)
Start indoors: Mar 23 Transplant: May 11 🍅 Harvest: Aug 24 – Sep 28
Recommended (50%) ✓ Fits season (15 days to spare)
Start indoors: Mar 31 Transplant: May 19 🍅 Harvest: Sep 1 – Oct 6
Safe Start (90%) ✓ Fits season (15 days to spare)
Start indoors: Apr 15 Transplant: Jun 3 🍅 Harvest: Sep 16 – Oct 21

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 Charlevoix County

How your county's soil matches Hubbard Squash's growing requirements.

Soil pH

Your soil pH (6.0โ€“6.8) is within Hubbard Squash's preferred range (6.0โ€“7.0).

Soil Texture

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

Organic Matter

Organic matter is excellent (4.2%) โ€” Hubbard Squash will thrive.

How to Plant Hubbard Squash

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

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
1.0″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft
Drought risk

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

Monthly Watering Guide for Hubbard Squash

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

Month Hubbard Squash Needs Rainfall You Supplement Action
Jan โ€” 1.7" 0" โ„๏ธ Dormant
Feb โ€” 2.1" 0" โ„๏ธ Dormant
Mar โ€” 2.8" 0" โ„๏ธ Dormant
Apr โ€” 3.7" 0" โ„๏ธ Dormant
May 4.3" 5.3" 0" โœ… Rainfall sufficient
Jun 4.3" 5.3" 0" โœ… Rainfall sufficient
Jul 4.3" 4.2" 0.1" ๐Ÿ’ง Light watering
Aug 4.3" 4.7" 0" โœ… Rainfall sufficient
Sep 4.3" 4.1" 0.2" ๐Ÿ’ง Light watering
Oct 4.3" 2.8" 1.5" ๐Ÿ’ง Light watering
Nov โ€” 2.7" 0" โ„๏ธ Dormant
Dec โ€” 2.5" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Mayโ€“Oct in Charlevoix County). Supplement amounts are based on average rainfall โ€” actual needs vary with temperature, soil, and mulching.

Hubbard Squash 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.

Hubbard Squash needs ~1,430 GDD — county provides 2,197 GDD Excellent fit

Hubbard Squash Planting Timeline โ€” Charlevoix County, MI

Hubbard Squash Planting Calendar

Activity When Date Range
Start Indoors March 31 Mar 31 โ€“ Apr 14
Transplant Outdoors May 19 May 19 โ€“ Jun 2
Direct Sow May 12 May 12 โ€“ Jun 2
Harvest September 1 Sep 1 โ€“ Oct 6

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

Month-by-Month Timeline

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

Growing Conditions

โ˜€๏ธ Sun

Full Sun (6-8+ hours)

๐Ÿ’ง Water

1"/week ยท Natural rainfall sufficient

๐Ÿ“… Days to Maturity

100โ€“120 days

๐Ÿงช Soil pH

Needs 6โ€“7 ยท Your soil: ideal

๐Ÿ—บ๏ธ USDA Zone

Zone 5a

๐Ÿ“† Growing Season

169 days in Charlevoix County

Growing Tips for Hubbard Squash in Charlevoix County

Direct sow Hubbard Squash outdoors after May 05 in Charlevoix County when soil has warmed and frost danger has passed.

Common pests for Hubbard Squash 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 in short-season areas. Requires ample space and rich soil. Harvest when the skin is very hard and the color is deep. Cure in the sun before storing.

Companion Planting

Good Companions

Avoid Planting Near

  • Potatoes

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Hubbard Squash in Charlevoix County, MI?

Charlevoix County is in Zone 5a with an average last frost of May 5. Plan your Hubbard Squash planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Charlevoix County, MI?

Charlevoix County, Michigan is in USDA Hardiness Zone 5a. The average last spring frost is May 5 and first fall frost is October 21.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Charlevoix County gardeners in Zone 5a 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 Charlevoix County, MI. Local conditions may vary. Last updated: April 2026.