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When to plant Hubbard Squash in Washington County, IL

In Zone 6b (Washington County), direct-sow Hubbard Squash between April 16 and May 7 for spring, after the April 9 last-frost mark.

When to Plant Hubbard Squash in Washington County, IL

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.

Washington County, Illinois is in USDA Zone 6b. The average last spring frost is April 9 and the first fall frost is October 20, giving you a growing season of approximately 194 days.

At an elevation of 1,126 feet, Washington County receives approximately 33.7 inches of rainfall annually with predominantly silt loam soil. Summer highs average 87°F, providing good warmth for Hubbard Squash during the growing season.

Washington County, IL (Zone 6b) Moderate season
194 days
Last Spring Frost April 9
194 growing days
First Fall Frost October 20

Washington County Soil Profile

Soil Type

Silt Loam

Soil pH

5.9-7.2

Drainage

Well Drained

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 1.3" 0" ❄️ Dormant
Feb 1.5" 0" ❄️ Dormant
Mar 2.4" 0" ❄️ Dormant
Apr 4.3" 3.7" 0.6" 💧 Light watering
May 4.3" 3.4" 0.9" 💧 Light watering
Jun 4.3" 4.3" 0" ✅ Rainfall sufficient
Jul 4.3" 3.9" 0.4" 💧 Light watering
Aug 4.3" 3.8" 0.5" 💧 Light watering
Sep 4.3" 2.8" 1.5" 💧 Light watering
Oct 4.3" 2.5" 1.8" 💧 Light watering
Nov 2.2" 0" ❄️ Dormant
Dec 1.8" 0" ❄️ Dormant

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

Hubbard Squash Planting Timeline — Washington County, IL

Hubbard Squash Planting Calendar

Activity When Date Range
Start Indoors March 5 Mar 5 – Mar 19
Transplant Outdoors April 23 Apr 23 – May 7
Direct Sow April 16 Apr 16 – May 7
Harvest August 6 Aug 6 – Sep 10

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

Month-by-Month Timeline

MonthActivities
January
February
March Start Indoors
April Transplant Outdoors 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

Moderate — regular watering

📅 Days to Maturity

100–120 days

🧪 Soil pH

Needs 6–7 · Your soil: N/A

🗺️ USDA Zone

Zone 6b

📆 Growing Season

194 days in Washington County

Growing Tips for Washington County

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 Washington County, IL?

Washington County is in Zone 6b with an average last frost of April 9. Plan your Hubbard Squash planting based on this frost date — see the calendar above for exact timing.

What planting zone is Washington County, IL?

Washington County, Illinois is in USDA Hardiness Zone 6b. The average last spring frost is April 9 and first fall frost is October 20.

When should I plant Hubbard Squash in Washington County, IL?

In Washington County, IL, plant Hubbard Squash after the last frost (around April 9) and before the first frost (around October 20). Best results when soil holds above 50°F.

What growing zone is Washington County, IL for Hubbard Squash?

Washington County sits in USDA Zone 6b. Hubbard Squash grows reliably in zones 3a through 10b, so it's a good fit here.

Can Hubbard Squash grow in Washington County's climate?

Yes — Hubbard Squash grows well in Washington County's temperate climate. Washington County averages a 194-day frost-free season, with last frost around April 9 and first frost around October 20.

🌱

Your Washington County Garden Planner — Free

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

Sources & credits

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