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When to Plant Chinese Cabbage in San Benito County, CA

San Benito County, California Zone 9b May

May in the garden — San Benito County, California

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

Avg. last frost February 21
Avg. first frost November 29
Soil temp (4") 76°F
Watering Critical
Pest pressure High
Daylight 14 hrs
  1. Basket week: chinese cabbage

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

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Chinese cabbage (Napa cabbage) forms elongated, barrel-shaped heads with tender, mild-flavored leaves. It is a staple in Asian cooking, particularly for kimchi.

San Benito County, California is in USDA Zone 9b. The average last spring frost is February 21 and the first fall frost is November 29, giving you a growing season of approximately 281 days.

At an elevation of 149 feet, San Benito County receives approximately 13 inches of rainfall annually with predominantly loam soil. Summer highs average 94°F, providing good warmth for Chinese Cabbage during the growing season. With low rainfall, drip irrigation is essential for growing Chinese Cabbage successfully. Mulch heavily to conserve soil moisture.

San Benito County, CA (Zone 9b) Year-round
281 days
Last Spring Frost February 21
281 growing days
First Fall Frost November 29

San Benito County Soil Profile

Soil Type

Loam

Soil pH

6.5-7.4

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (206 days to spare)
Start indoors: Jan 8 Transplant: Feb 5 🍅 Harvest: Apr 2 – Apr 30
Recommended (50%) ✓ Fits season (197 days to spare)
Start indoors: Jan 24 Transplant: Feb 21 🍅 Harvest: Apr 18 – May 16
Safe Start (90%) ✓ Fits season (173 days to spare)
Start indoors: Mar 11 Transplant: Apr 8 🍅 Harvest: Jun 3 – Jul 1

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 Benito County

How your county's soil matches Chinese Cabbage's growing requirements.

Soil pH

Your soil pH (6.5–7.4) is within Chinese Cabbage's preferred range (6.0–7.5).

Soil Texture

The loam soil in San Benito County is excellent for Chinese Cabbage — good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is moderate (2.7%). Annual compost additions will help Chinese Cabbage.

How to Plant Chinese Cabbage

1"
Planting Depth
15"
Between Plants
24"
Between Rows

Fall planting: Sow 8 weeks before your first frost date for a fall harvest.

Succession Planting Chinese Cabbage

6
successive plantings in your 281-day season

Sow every 5.7 weeks. Last sowing by Sep 20 to harvest before frost.

For a dedicated fall crop, sow by Oct 04.

Plant Water Budget

Plant needs
1.5″/week
Rainfall provides
0.2″/week
You supply
1.6″/week
Watering frequency 2-3 times/week
Season total 3,935 gal / 100 sq ft
Drought risk

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

Monthly Watering Guide for Chinese Cabbage

Chinese Cabbage needs approximately 1.5 inches of water per week (6.5" per month). Here's how your county's rainfall compares month by month.

Month Chinese Cabbage Needs Rainfall You Supplement Action
Jan 2.5" 0" ❄️ Dormant
Feb 6.5" 2.6" 3.9" 🚿 Regular watering
Mar 6.5" 2.2" 4.3" 🚿 Regular watering
Apr 6.5" 1.1" 5.4" 🚿 Regular watering
May 6.5" 0.3" 6.2" 🚿 Regular watering
Jun 6.5" 0.1" 6.4" 🚿 Regular watering
Jul 6.5" 0" 6.5" 🚿 Regular watering
Aug 6.5" 0" 6.5" 🚿 Regular watering
Sep 6.5" 0.1" 6.4" 🚿 Regular watering
Oct 6.5" 0.5" 6" 🚿 Regular watering
Nov 6.5" 1.3" 5.2" 🚿 Regular watering
Dec 2.3" 0" ❄️ Dormant

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

Chinese Cabbage 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.

Chinese Cabbage needs ~1,230 GDD — county provides 5,781 GDD Excellent fit

Chinese Cabbage Planting Timeline — San Benito County, CA

Chinese Cabbage Planting Calendar

Activity When Date Range
Start Indoors January 24 Jan 24 – Feb 7
Transplant Outdoors February 21 Feb 21 – Mar 7
Direct Sow January 31 Jan 31 – Feb 21
Harvest April 18 Apr 18 – May 16
Fall Sowing October 4 Oct 4 – Oct 18

Plant 1" deep · 15" apart · Rows 24" apart

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Partial Shade (3-6 hours)

💧 Water

1.5"/week · 2-3 times/week

📅 Days to Maturity

50–70 days

🧪 Soil pH

Needs 6–7.5 · Your soil: ideal

🗺️ USDA Zone

Zone 9b

📆 Growing Season

281 days in San Benito County

Growing Tips for Chinese Cabbage in San Benito County

Direct sow Chinese Cabbage outdoors after February 21 in San Benito County when soil has warmed and frost danger has passed.

Common pests for Chinese Cabbage in this region include cabbage worm and flea beetles. Use row covers early in the season and inspect plants weekly.

San Benito County receives only 13" of rain annually. Chinese Cabbage needs consistent moisture — install drip irrigation or water deeply 2-3 times per week.

General growing tips

Best grown as a fall crop to avoid bolting. Start seeds indoors or direct sow in late summer. Keep soil consistently moist and provide shade in warm weather.

Companion Planting

Good Companions

Avoid Planting Near

  • Strawberries
  • Tomatoes

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Chinese Cabbage in San Benito County, CA?

San Benito County is in Zone 9b with an average last frost of February 21. Plan your Chinese Cabbage planting based on this frost date — see the calendar above for exact timing.

What planting zone is San Benito County, CA?

San Benito County, California is in USDA Hardiness Zone 9b. The average last spring frost is February 21 and first fall frost is November 29.

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Your San Benito County Garden Planner — Free

A 24-page printable planner built for San Benito County (Zone 9b). 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 Benito County, CA. 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.