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When to Plant Pac Choi in Modoc County, CA

Pac choi (baby bok choy) is a compact variety of Chinese cabbage with tender leaves and crisp stems. It grows quickly and is ideal for containers and small spaces.

Modoc County, California is in USDA Zone 6a. The average last spring frost is May 31 and the first fall frost is September 21, giving you a growing season of approximately 113 days.

At an elevation of 2,205 feet, Modoc County receives approximately 28.3 inches of rainfall annually with predominantly loam soil. Summer highs average 83ยฐF, so choose short-season varieties of Pac Choi to ensure they mature before fall.

Modoc County, CA (Zone 6a) Short season
113 days
Last Spring Frost May 31
113 growing days
First Fall Frost September 21

Modoc County Soil Profile

Soil Type

Loam

Soil pH

5.9-7.4

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (50 days to spare)
Start indoors: Apr 14 Transplant: May 19 🍅 Harvest: Jun 30 – Jul 28
Recommended (50%) ✓ Fits season (43 days to spare)
Start indoors: Apr 26 Transplant: May 31 🍅 Harvest: Jul 12 – Aug 9
Safe Start (90%) ✓ Fits season (49 days to spare)
Start indoors: May 15 Transplant: Jun 19 🍅 Harvest: Jul 31 – Aug 28

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 Modoc County

How your county's soil matches Pac Choi's growing requirements.

Soil pH

Your soil pH (5.9โ€“7.4) overlaps with Pac Choi's range (6.0โ€“7.5), though not a perfect match.

Soil Texture

The loam soil in Modoc County is excellent for Pac Choi โ€” good drainage, moisture retention, and nutrient holding capacity.

Drainage

Pac Choi is a heavy drinker but your soil drains very quickly. Mulch heavily and consider drip irrigation.

Organic Matter

Organic matter is moderate (2.1%). Annual compost additions will help Pac Choi.

How to Plant Pac Choi

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

Fall planting: Sow 10 weeks before your first frost date for a fall harvest.

Succession Planting Pac Choi

3
successive plantings in your 113-day season

Sow every 4.6 weeks. Last sowing by Jul 28 to harvest before frost.

For a dedicated fall crop, sow by Jul 13.

Plant Water Budget

Plant needs
1.5″/week
Rainfall provides
1.1″/week
You supply
1.1″/week
Watering frequency 2-3 times/week
Season total 1,084 gal / 100 sq ft
Drought risk

Water stress score is 8/10 โ€” consider drought-tolerant varieties and mulching

Monthly Watering Guide for Pac Choi

Pac Choi 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 Pac Choi Needs Rainfall You Supplement Action
Jan โ€” 5.6" 0" โ„๏ธ Dormant
Feb โ€” 5.8" 0" โ„๏ธ Dormant
Mar โ€” 4.1" 0" โ„๏ธ Dormant
Apr โ€” 2.1" 0" โ„๏ธ Dormant
May 6.5" 0.7" 5.8" ๐Ÿšฟ Regular watering
Jun 6.5" 0.1" 6.4" ๐Ÿšฟ Regular watering
Jul 6.5" 0" 6.5" ๐Ÿšฟ Regular watering
Aug 6.5" 0" 6.5" ๐Ÿšฟ Regular watering
Sep 6.5" 0.4" 6.1" ๐Ÿšฟ Regular watering
Oct โ€” 1.3" 0" โ„๏ธ Dormant
Nov โ€” 2.7" 0" โ„๏ธ Dormant
Dec โ€” 5.5" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Mayโ€“Sep in Modoc County). Supplement amounts are based on average rainfall โ€” actual needs vary with temperature, soil, and mulching.

Pac Choi 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.

Pac Choi needs ~582 GDD — county provides 1,384 GDD Excellent fit

Pac Choi Planting Timeline โ€” Modoc County, CA

Pac Choi Planting Calendar

Activity When Date Range
Start Indoors April 26 Apr 26 โ€“ May 10
Transplant Outdoors May 31 May 31 โ€“ Jun 14
Direct Sow May 17 May 17 โ€“ Jun 7
Harvest July 12 Jul 12 โ€“ Aug 9
Fall Sowing July 13 Jul 13 โ€“ Jul 27

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

Month-by-Month Timeline

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

Growing Conditions

โ˜€๏ธ Sun

Partial Shade (3-6 hours)

๐Ÿ’ง Water

1.5"/week ยท 2-3 times/week

๐Ÿ“… Days to Maturity

40โ€“55 days

๐Ÿงช Soil pH

Needs 6โ€“7.5 ยท Your soil: acceptable

๐Ÿ—บ๏ธ USDA Zone

Zone 6a

๐Ÿ“† Growing Season

113 days in Modoc County

Growing Tips for Pac Choi in Modoc County

Direct sow Pac Choi outdoors after May 31 in Modoc County when soil has warmed and frost danger has passed.

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

General growing tips

Direct sow in spring or fall. Grows best in cool weather. Space 6 inches apart for baby pac choi. Harvest whole plants or cut outer leaves as needed.

Companion Planting

Good Companions

Avoid Planting Near

  • Strawberries

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Pac Choi in Modoc County, CA?

Modoc County is in Zone 6a with an average last frost of May 31. Plan your Pac Choi planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Modoc County, CA?

Modoc County, California is in USDA Hardiness Zone 6a. The average last spring frost is May 31 and first fall frost is September 21.

๐ŸŒฑ

Plan Your Garden with Confidence

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

Get Your Free Garden Planner →

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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 Modoc County, CA. Local conditions may vary. Last updated: April 2026.