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When to Plant Hubbard Squash in Carroll County, IN

Carroll County, Indiana Zone 6a May

May in Carroll County, Indiana — your action list

May is a pivotal month for Carroll County, Indiana gardens. Focus on these tasks first and you'll set up the rest of the season for success.

Avg. last frost April 23
Avg. first frost October 16
Soil temp (4") 59°F
Watering Low
Pest pressure Low
Daylight 14.3 hrs
  1. Set out hubbard squash seedlings

    Water the tray well an hour before you transplant. Roots slide out cleanly and settle in faster.

  2. Get hubbard squash seeds going inside

    Your window is short. These crops want several weeks of indoor growth before they go outside.

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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.

Carroll County, Indiana is in USDA Zone 6a. The average last spring frost is April 23 and the first fall frost is October 16, giving you a growing season of approximately 176 days.

At an elevation of 1,252 feet, Carroll County receives approximately 41.7 inches of rainfall annually with predominantly silt loam soil. Summer highs average 83°F, so choose short-season varieties of Hubbard Squash to ensure they mature before fall.

Carroll County, IN (Zone 6a) Moderate season
176 days
Last Spring Frost April 23
176 growing days
First Fall Frost October 16

Carroll County Soil Profile

Soil Type

Silt Loam

Soil pH

5.8-6.8

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (22 days to spare)
Start indoors: Mar 14 Transplant: May 2 🍅 Harvest: Aug 15 – Sep 19
Recommended (50%) ✓ Fits season (22 days to spare)
Start indoors: Mar 19 Transplant: May 7 🍅 Harvest: Aug 20 – Sep 24
Safe Start (90%) ✓ Fits season (22 days to spare)
Start indoors: Apr 2 Transplant: May 21 🍅 Harvest: Sep 3 – Oct 8

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 Carroll County

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

Soil pH

Your soil pH (5.8–6.8) overlaps with Hubbard Squash's range (6.0–7.0), though not a perfect match.

Soil Texture

The silt loam soil in Carroll County is excellent for Hubbard Squash — good drainage, moisture retention, and nutrient holding capacity.

Drainage

Drainage is adequate for Hubbard Squash.

Organic Matter

Organic matter is excellent (4.1%) — 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
You supply
0.3″/week
Watering frequency 1-2 times/week
Season total 478 gal / 100 sq ft

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 1.5" 0" ❄️ Dormant
Feb 2" 0" ❄️ Dormant
Mar 2.6" 0" ❄️ Dormant
Apr 4.3" 3.6" 0.7" 💧 Light watering
May 4.3" 5.4" 0" ✅ Rainfall sufficient
Jun 4.3" 5.7" 0" ✅ Rainfall sufficient
Jul 4.3" 4.4" 0" ✅ Rainfall sufficient
Aug 4.3" 4.9" 0" ✅ Rainfall sufficient
Sep 4.3" 3.4" 0.9" 💧 Light watering
Oct 4.3" 3.2" 1.1" 💧 Light watering
Nov 2.8" 0" ❄️ Dormant
Dec 2.2" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Carroll County). Supplement amounts are based on average rainfall — 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" — 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.

Hubbard Squash needs ~1,348 GDD — county provides 2,156 GDD Excellent fit

Hubbard Squash Planting Timeline — Carroll County, IN

Hubbard Squash Planting Calendar

Activity When Date Range
Start Indoors March 19 Mar 19 – Apr 2
Transplant Outdoors May 7 May 7 – May 21
Direct Sow April 30 Apr 30 – May 21
Harvest August 20 Aug 20 – Sep 24

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

Month-by-Month Timeline

MonthActivities
January
February
March Start Indoors
April Start Indoors Direct Sow
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 · 1-2 times/week

📅 Days to Maturity

100–120 days

🧪 Soil pH

Needs 6–7 · Your soil: acceptable

🗺️ USDA Zone

Zone 6a

📆 Growing Season

176 days in Carroll County

Growing Tips for Hubbard Squash in Carroll County

Direct sow Hubbard Squash outdoors after April 23 in Carroll 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 Carroll County, IN?

Carroll County is in Zone 6a with an average last frost of April 23. Plan your Hubbard Squash planting based on this frost date — see the calendar above for exact timing.

What planting zone is Carroll County, IN?

Carroll County, Indiana is in USDA Hardiness Zone 6a. The average last spring frost is April 23 and first fall frost is October 16.

🌱

Your Carroll County Garden Planner — Free

A 24-page printable planner built for Carroll 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 Carroll County, IN. 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.