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When to Plant Kabocha in San Jacinto County, TX

San Jacinto County, Texas Zone 9a May

May in the garden — San Jacinto County, Texas

Welcome to May in Zone 9a. These are the moves that will have the biggest impact on your growing season.

Avg. last frost February 18
Avg. first frost December 1
Soil temp (4") 71°F
Watering Low
Pest pressure High
Daylight 13.5 hrs
  1. Collect kabocha at their peak

    Check every 1–2 days. Many of these get tough or go to seed if you wait too long.

Get ahead of June
  • First harvests: kabocha

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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.

San Jacinto County, Texas is in USDA Zone 9a. The average last spring frost is February 18 and the first fall frost is December 1, giving you a growing season of approximately 286 days.

At an elevation of 6 feet, San Jacinto County receives approximately 71.3 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 94°F, providing good warmth for Kabocha during the growing season. Sandy soil warms quickly in spring — great for early planting — but Kabocha will need more frequent watering and organic matter to retain nutrients. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Kabocha root diseases.

San Jacinto County, TX (Zone 9a) Year-round
286 days
Last Spring Frost February 18
286 growing days
First Fall Frost December 1
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San Jacinto County Soil Profile

Soil Type

Sandy Loam

Soil pH

5.3-6.7

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (161 days to spare)
Start indoors: Jan 13 Transplant: Feb 17 🍅 Harvest: May 19 – Jun 16
Recommended (50%) ✓ Fits season (160 days to spare)
Start indoors: Jan 21 Transplant: Feb 25 🍅 Harvest: May 27 – Jun 24
Safe Start (90%) ✓ Fits season (157 days to spare)
Start indoors: Feb 9 Transplant: Mar 16 🍅 Harvest: Jun 15 – Jul 13

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 San Jacinto County

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

Soil pH

Your soil pH (5.3–6.7) overlaps with Kabocha's range (6.0–7.5), though not a perfect match.

Soil Texture

Sandy soil in San Jacinto County warms quickly in spring but drains fast. Kabocha will need more frequent watering and regular compost additions to retain nutrients.

Organic Matter

Organic matter is moderate (2.2%). 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 — 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 1.7" 0" ❄️ Dormant
Feb 4.3" 2.5" 1.8" 💧 Light watering
Mar 4.3" 4.2" 0.1" 💧 Light watering
Apr 4.3" 8.5" 0" ✅ Rainfall sufficient
May 4.3" 9.5" 0" ✅ Rainfall sufficient
Jun 4.3" 11.4" 0" ✅ Rainfall sufficient
Jul 4.3" 9.2" 0" ✅ Rainfall sufficient
Aug 4.3" 8" 0" ✅ Rainfall sufficient
Sep 4.3" 6.7" 0" ✅ Rainfall sufficient
Oct 4.3" 5.2" 0" ✅ Rainfall sufficient
Nov 4.3" 2.6" 1.7" 💧 Light watering
Dec 4.3" 1.9" 2.4" 🚿 Regular watering

Water needs are for active growing months only (Feb–Dec in San Jacinto 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 ~1,896 GDD — county provides 5,883 GDD Excellent fit

Kabocha Planting Timeline — San Jacinto County, TX

Kabocha Planting Calendar

Activity When Date Range
Start Indoors January 21 Jan 21 – Feb 4
Transplant Outdoors February 25 Feb 25 – Mar 11
Direct Sow February 18 Feb 18 – Mar 11
Harvest May 27 May 27 – Jun 24

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

Month-by-Month Timeline

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

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

1"/week · Natural rainfall sufficient

📅 Days to Maturity

85–100 days

🧪 Soil pH

Needs 6–7.5 · Your soil: acceptable

🗺️ USDA Zone

Zone 9a

📆 Growing Season

286 days in San Jacinto County

Growing Tips for Kabocha in San Jacinto County

Direct sow Kabocha outdoors after February 18 in San Jacinto County when soil has warmed and frost danger has passed.

Sandy soil in San Jacinto County dries quickly — mulch Kabocha with 2-3 inches of straw and water deeply 2-3 times per week rather than lightly every day.

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 San Jacinto County, TX?

San Jacinto County is in Zone 9a with an average last frost of February 18. Plan your Kabocha planting based on this frost date — see the calendar above for exact timing.

What planting zone is San Jacinto County, TX?

San Jacinto County, Texas is in USDA Hardiness Zone 9a. The average last spring frost is February 18 and first fall frost is December 1.

🌱

Your San Jacinto County Garden Planner — Free

A 24-page printable planner built for San Jacinto County (Zone 9a). 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 San Jacinto County, TX. Local conditions may vary. Last updated: May 2026.

Sources & credits

Every number on this page traces back to a primary horticulture or government data source. Click through to verify.