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When to Plant Kabocha in USDA Zone 10b

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.

In Zone 10b, the average last spring frost is around January 1 and the first fall frost is around December 31, giving you a growing season of approximately 364 days.

Zone 10b Year-round
364 days
Last Spring Frost January 1
364 growing days
First Fall Frost December 31

Kabocha Planting Timeline — Zone 10b

Where Is USDA Zone 10b?

The map below highlights the states that contain Zone 10b. Click any state to see the Kabocha planting schedule for that location.

Prints a clean, ink-friendly version without maps or navigation.

Kabocha Planting Calendar — Zone 10b

Activity When Date Range
Start Indoors December 4 Dec 4 – Dec 18
Transplant Outdoors January 8 Jan 8 – Jan 22
Direct Sow January 1 Jan 1 – Jan 22
Harvest April 9 Apr 9 – May 7

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

Month-by-Month Timeline

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

Free Zone 10b Planting Calendar PDF

Know exactly when to plant every crop in your zone. Get a printable month-by-month calendar customized for Zone 10b with start dates, transplant windows, and harvest times.

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Growing Conditions

Sun

Full Sun (6-8+ hours)

💧 Water

Moderate — regular watering

Days to Maturity

85–100 days

Soil pH

6 – 7.5

Zone Temperature Range

35°F to 40°F average annual minimum

Growing Season

364 days (Zone 10b average)

Planting Specifications

Planting Depth1 inches
Plant Spacing30 inches apart
Row Spacing42 inches between rows

Growing Tips for Kabocha in Zone 10b

Zone 10b offers a long growing season (~364 days). You can plant Kabocha earlier and may get multiple harvests.

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

Level Up Your Garden

Saving Kabocha Seeds

Recommended for Your Garden

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Garden Shade Cloth $15-35

Reduce heat stress and sun scorch in hot climates with UV-stabilized shade cloth.

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Seed Starting Trays $8-20

Start seeds indoors with reusable cell trays and humidity domes.

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Soil Test Kit $12-25

Test your soil pH, nitrogen, phosphorus, and potassium levels before planting.

Related Plants

Frequently Asked Questions

When should I plant Kabocha in Zone 10b?

In Zone 10b, plan your Kabocha planting around the average last frost date of January 1. Start seeds indoors around December 4. Direct sow outdoors around January 1. Transplant seedlings around January 8.

Can Kabocha grow in Zone 10b?

Yes, Kabocha can grow well in Zone 10b, hardy in USDA zones 3a through 11b. Zone 10b has a growing season of approximately 364 days, which is sufficient for Kabocha (85-100 days to maturity).

When can I harvest Kabocha in Zone 10b?

In Zone 10b, expect to harvest Kabocha from April 9 – May 7. Kabocha takes 85-100 days from planting to harvest.

What is the last frost date for Zone 10b?

The average last spring frost in Zone 10b is around January 1, and the first fall frost is around December 31. This gives a growing season of approximately 364 days. These are 50% probability dates — actual frost dates vary year to year.

What should I plant next to Kabocha?

Good companion plants for Kabocha include Corn, Green Beans, Radish. These companions can help with pest control, pollination, and nutrient sharing.

🌱

Plan Your Garden with Confidence

Get our free Garden Planner — organize your planting dates for Zone 10b, track your crops, and plan your garden season from seed to harvest.

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Free download. Plan your entire garden season in minutes.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals, University Cooperative Extension planting guides. Planting dates are estimates based on average frost dates — local conditions may vary. Last updated: April 2026.