Blog

When to plant Kabocha in Compton, IL

Spring Kabocha in Compton goes in April 29–May 20, once nighttime temps stop dipping near freezing.

When to Plant Kabocha in Compton, IL

Lee County, Illinois Zone 5b August

What to do in August

We've pulled the most time-sensitive tasks for Lee County, Illinois this August and put them front and centre. Tackle them in order.

Avg. last frost April 22
Avg. first frost October 14
Soil temp (4") 78°F
Watering Moderate
Pest pressure High
Daylight 13.7 hrs
  1. Start harvesting kabocha

    Don't tug. Use scissors or pruners for clean cuts — torn stems invite disease.

Coming up in September — start thinking about
  • First harvests: kabocha

Instant PDF download. No spam, unsubscribe any time.

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.

Compton, Illinois is in USDA Zone 5b. The average last spring frost is April 22 and the first fall frost is October 14, giving you a growing season of approximately 175 days.

At an elevation of 1,010 feet, Lee County receives approximately 33.6 inches of rainfall annually with predominantly silt loam soil. Summer highs average 84°F, so choose short-season varieties of Kabocha to ensure they mature before fall.

Compton, IL (Zone 5b) Moderate season
175 days
Last Spring Frost April 22
175 growing days
First Fall Frost October 14

Compton Soil Profile

Soil Type

Silt Loam

Soil pH

6.3-6.9

Drainage

Well Drained

Kabocha Planting Risk Windows

Early Start (70% safe) ✓ Fits season (43 days to spare)
Start indoors: Mar 13 Transplant: May 1 🍅 Harvest: Jul 31 – Aug 28
Recommended (50%) ✓ Fits season (42 days to spare)
Start indoors: Mar 18 Transplant: May 6 🍅 Harvest: Aug 5 – Sep 2
Safe Start (90%) ✓ Fits season (43 days to spare)
Start indoors: Mar 31 Transplant: May 19 🍅 Harvest: Aug 18 – Sep 15

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 Compton

How your county's soil matches Kabocha's growing requirements.

Soil pH

Your soil pH (6.3–6.9) is within Kabocha's preferred range (6.0–7.5).

Soil Texture

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

Drainage

Drainage is adequate for Kabocha.

Organic Matter

Organic matter is excellent (4.8%) — Kabocha will thrive.

How to Plant Kabocha

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

Kabocha Water Budget

Plant needs
1.0″/week
Rainfall provides
0.8″/week
You supply
0.6″/week
Watering frequency 1-2 times/week
Season total 923 gal / 100 sq ft
Drought risk

Water stress score is 6/10 — consider drought-tolerant varieties and mulching

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 1.6" 0" ❄️ Dormant
Feb 1.6" 0" ❄️ Dormant
Mar 2" 0" ❄️ Dormant
Apr 4.3" 2.8" 1.5" 💧 Light watering
May 4.3" 4.4" 0" ✅ Rainfall sufficient
Jun 4.3" 4.2" 0.1" 💧 Light watering
Jul 4.3" 3.3" 1" 💧 Light watering
Aug 4.3" 3.5" 0.8" 💧 Light watering
Sep 4.3" 2.9" 1.4" 💧 Light watering
Oct 4.3" 2.7" 1.6" 💧 Light watering
Nov 2.7" 0" ❄️ Dormant
Dec 1.8" 0" ❄️ Dormant

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

Kabocha 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.

Kabocha needs ~1,202 GDD — county provides 2,275 GDD Excellent fit

Kabocha Planting Timeline — Compton, IL

Kabocha Planting Calendar

Activity When Date Range
Start Indoors March 18 Mar 18 – Apr 1
Transplant Outdoors May 6 May 6 – May 20
Direct Sow April 29 Apr 29 – May 20
Harvest August 5 Aug 5 – Sep 2

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

85–100 days

🧪 Soil pH

Needs 6–7.5 · Your soil: ideal

🗺️ USDA Zone

Zone 5b

📆 Growing Season

175 days in Lee County

Growing Tips for Kabocha in Compton

Direct sow Kabocha outdoors after April 22 in Lee County when soil has warmed and frost danger has passed.

Common pests for Kabocha in this region include squash vine borer and cucumber beetles. Use row covers early in the season and inspect plants weekly.

General growing tips

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 →

When should I plant Kabocha in Compton, IL?

In Compton, IL, plant Kabocha after the last frost (around April 22) and before the first frost (around October 14). Best results when soil holds above 50°F.

What growing zone is Compton, IL for Kabocha?

Compton sits in USDA Zone 5b. Kabocha grows reliably in zones 3a through 11b, so it's a good fit here.

Can Kabocha grow in Compton's climate?

Yes — Kabocha grows well in Compton's temperate climate. Compton averages a 175-day frost-free season, with last frost around April 22 and first frost around October 14.

🌱

Your Lee County Garden Planner — Free

A 22-page printable planner built for Lee County (Zone 5b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.

Instant PDF download. No spam, unsubscribe any time.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Lee County, IL. Local conditions may vary. Last updated: August 2026.