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When to Plant Kabocha in Vermilion County, IL

Kabocha is a Japanese winter squash with an exceptionally sweet, dense, chestnut-like flesh and dark green skin. It is a favorite in Asian cuisine for its rich, dry texture.

Vermilion County, Illinois is in USDA Zone 5b. The average last spring frost is April 14 and the first fall frost is October 16, giving you a growing season of approximately 185 days.

At an elevation of 1,218 feet, Vermilion County receives approximately 31.2 inches of rainfall annually with predominantly silt loam soil. Summer highs average 85ยฐF, providing good warmth for Kabocha during the growing season.

Vermilion County, IL (Zone 5b) Moderate season
185 days
Last Spring Frost April 14
185 growing days
First Fall Frost October 16

Vermilion County Soil Profile

Soil Type

Silt Loam

Soil pH

6.2-6.9

Drainage

Well Drained

Monthly Watering Guide for Kabocha

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

Month Kabocha Needs Rainfall You Supplement Action
Jan โ€” 1.4" 0" โ„๏ธ Dormant
Feb โ€” 1.4" 0" โ„๏ธ Dormant
Mar โ€” 1.8" 0" โ„๏ธ Dormant
Apr 4.3" 3.1" 1.2" ๐Ÿ’ง Light watering
May 4.3" 3.9" 0.4" ๐Ÿ’ง Light watering
Jun 4.3" 3.7" 0.6" ๐Ÿ’ง Light watering
Jul 4.3" 3.8" 0.5" ๐Ÿ’ง Light watering
Aug 4.3" 3.5" 0.8" ๐Ÿ’ง Light watering
Sep 4.3" 2.5" 1.8" ๐Ÿ’ง Light watering
Oct 4.3" 2.1" 2.2" ๐Ÿšฟ Regular watering
Nov โ€” 2.2" 0" โ„๏ธ Dormant
Dec โ€” 1.7" 0" โ„๏ธ Dormant

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

Kabocha Planting Timeline โ€” Vermilion County, IL

Kabocha Planting Calendar

Activity When Date Range
Start Indoors March 10 Mar 10 โ€“ Mar 24
Transplant Outdoors April 28 Apr 28 โ€“ May 12
Direct Sow April 21 Apr 21 โ€“ May 12
Harvest July 28 Jul 28 โ€“ Aug 25

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

Month-by-Month Timeline

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

Growing Conditions

โ˜€๏ธ Sun

Full Sun (6-8+ hours)

๐Ÿ’ง Water

Moderate โ€” regular watering

๐Ÿ“… Days to Maturity

85โ€“100 days

๐Ÿงช Soil pH

Needs 6โ€“7.5 ยท Your soil: N/A

๐Ÿ—บ๏ธ USDA Zone

Zone 5b

๐Ÿ“† Growing Season

185 days in Vermilion County

Growing Tips for Vermilion County

Direct sow after frost or start indoors. Harvest when the skin is hard and dull. The stem should be dry and corky. Stores well for 3-4 months in a cool, dry place.

Companion Planting

Good Companions

Avoid Planting Near

  • Potatoes

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Kabocha in Vermilion County, IL?

Vermilion County is in Zone 5b with an average last frost of April 14. Plan your Kabocha planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Vermilion County, IL?

Vermilion County, Illinois is in USDA Hardiness Zone 5b. The average last spring frost is April 14 and first fall frost is October 16.

๐ŸŒฑ

Plan Your Garden with Confidence

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