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When to Plant Kabocha in Graves County, KY

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.

Graves County, Kentucky is in USDA Zone 6b. The average last spring frost is March 28 and the first fall frost is October 31, giving you a growing season of approximately 217 days.

At an elevation of 1,433 feet, Graves County receives approximately 53 inches of rainfall annually with predominantly silt loam soil. Summer highs average 85ยฐF, providing good warmth for Kabocha during the growing season. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Kabocha root diseases.

Graves County, KY (Zone 6b) Long season
217 days
Last Spring Frost March 28
217 growing days
First Fall Frost October 31

Graves County Soil Profile

Soil Type

Silt Loam

Soil pH

5.2-6.9

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (87 days to spare)
Start indoors: Feb 12 Transplant: Apr 2 🍅 Harvest: Jul 2 – Jul 30
Recommended (50%) ✓ Fits season (84 days to spare)
Start indoors: Feb 21 Transplant: Apr 11 🍅 Harvest: Jul 11 – Aug 8
Safe Start (90%) ✓ Fits season (78 days to spare)
Start indoors: Mar 11 Transplant: Apr 29 🍅 Harvest: Jul 29 – Aug 26

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 Graves County

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

Soil pH

Your soil pH (5.2โ€“6.9) overlaps with Kabocha's range (6.0โ€“7.5), though not a perfect match.

Soil Texture

The silt loam soil in Graves County is excellent for Kabocha โ€” good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is moderate (2.4%). Annual compost additions will help Kabocha.

How to Plant Kabocha

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

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
1.0″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft
Drought risk

Water stress score is 6/10 โ€” 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 โ€” 3.7" 0" โ„๏ธ Dormant
Feb โ€” 4.5" 0" โ„๏ธ Dormant
Mar 4.3" 5" 0" โœ… Rainfall sufficient
Apr 4.3" 4.2" 0.1" ๐Ÿ’ง Light watering
May 4.3" 4.6" 0" โœ… Rainfall sufficient
Jun 4.3" 5" 0" โœ… Rainfall sufficient
Jul 4.3" 5.7" 0" โœ… Rainfall sufficient
Aug 4.3" 4.2" 0.1" ๐Ÿ’ง Light watering
Sep 4.3" 4" 0.3" ๐Ÿ’ง Light watering
Oct 4.3" 3.4" 0.9" ๐Ÿ’ง Light watering
Nov โ€” 4.1" 0" โ„๏ธ Dormant
Dec โ€” 4.7" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Marโ€“Oct in Graves County). Supplement amounts are based on average rainfall โ€” 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" โ€” every day above 50ยฐF 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 ~1,272 GDD — county provides 2,983 GDD Excellent fit

Kabocha Planting Timeline โ€” Graves County, KY

Kabocha Planting Calendar

Activity When Date Range
Start Indoors February 21 Feb 21 โ€“ Mar 7
Transplant Outdoors April 11 Apr 11 โ€“ Apr 25
Direct Sow April 4 Apr 4 โ€“ Apr 25
Harvest July 11 Jul 11 โ€“ Aug 8

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

Month-by-Month Timeline

MonthActivities
January โ€”
February Start Indoors
March Start Indoors
April Transplant Outdoors Direct Sow
May โ€”
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

1"/week ยท Natural rainfall sufficient

๐Ÿ“… Days to Maturity

85โ€“100 days

๐Ÿงช Soil pH

Needs 6โ€“7.5 ยท Your soil: acceptable

๐Ÿ—บ๏ธ USDA Zone

Zone 6b

๐Ÿ“† Growing Season

217 days in Graves County

Growing Tips for Kabocha in Graves County

Direct sow Kabocha outdoors after March 28 in Graves 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 →

Frequently Asked Questions

When should I plant Kabocha in Graves County, KY?

Graves County is in Zone 6b with an average last frost of March 28. Plan your Kabocha planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Graves County, KY?

Graves County, Kentucky is in USDA Hardiness Zone 6b. The average last spring frost is March 28 and first fall frost is October 31.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Graves County gardeners in Zone 6b organize planting dates, track what's growing, and never miss a planting window.

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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 Graves County, KY. Local conditions may vary. Last updated: April 2026.