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When to plant Squash (Summer) in Douglas County, IL

In Zone 6a (Douglas County), direct-sow Squash (Summer) between April 21 and May 12 for spring, after the April 14 last-frost mark.

When to Plant Squash (Summer) in Douglas County, IL

Summer squash includes zucchini, yellow crookneck, and pattypan varieties that are harvested young and tender. They are prolific producers in warm weather.

Douglas County, Illinois is in USDA Zone 6a. The average last spring frost is April 14 and the first fall frost is October 17, giving you a growing season of approximately 186 days.

At an elevation of 1,036 feet, Douglas County receives approximately 30.9 inches of rainfall annually with predominantly silt loam soil. Summer highs average 87°F, providing good warmth for Squash (Summer) during the growing season.

Douglas County, IL (Zone 6a) Moderate season
186 days
Last Spring Frost April 14
186 growing days
First Fall Frost October 17

Douglas County Soil Profile

Soil Type

Silt Loam

Soil pH

6.0-7.0

Drainage

Well Drained

Squash (Summer) Planting Timeline — Douglas County, IL

Squash (Summer) Planting Calendar

Activity When Date Range
Start Indoors March 10 Mar 10 – Mar 24
Transplant Outdoors April 28 Apr 28 – May 12
Direct Sow April 21 Apr 21 – May 12
Harvest June 16 Jun 16 – Aug 18

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 Harvest
July Harvest
August Harvest
September
October
November
December

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

Moderate — regular watering

📅 Days to Maturity

45–65 days

🧪 Soil pH

Needs 6–7.5 · Your soil: N/A

🗺️ USDA Zone

Zone 6a

📆 Growing Season

186 days in Douglas County

Growing Tips for Douglas County

Direct sow after last frost on mounds. Harvest frequently when fruits are 6-8 inches for best texture. Check plants daily as they grow rapidly in summer heat.

Companion Planting

Good Companions

Avoid Planting Near

  • Potatoes

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Squash (Summer) in Douglas County, IL?

Douglas County is in Zone 6a with an average last frost of April 14. Plan your Squash (Summer) planting based on this frost date — see the calendar above for exact timing.

What planting zone is Douglas County, IL?

Douglas County, Illinois is in USDA Hardiness Zone 6a. The average last spring frost is April 14 and first fall frost is October 17.

When should I plant Squash (Summer) in Douglas County, IL?

In Douglas County, IL, plant Squash (Summer) after the last frost (around April 14) and before the first frost (around October 17). Best results when soil holds above 50°F.

What growing zone is Douglas County, IL for Squash (Summer)?

Douglas County sits in USDA Zone 6a. Squash (Summer) grows reliably in zones 3a through 11b, so it's a good fit here.

Can Squash (Summer) grow in Douglas County's climate?

Yes — Squash (Summer) grows well in Douglas County's temperate climate. Douglas County averages a 186-day frost-free season, with last frost around April 14 and first frost around October 17.

🌱

Your Douglas County Garden Planner — Free

A 22-page printable planner built for Douglas 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 Douglas County, IL. Local conditions may vary. Last updated: June 2026.

Sources & credits

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