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When to Plant Pac Choi in Washington County, IL

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.

Washington County, Illinois is in USDA Zone 6a. The average last spring frost is April 9 and the first fall frost is October 20, giving you a growing season of approximately 194 days.

At an elevation of 1,126 feet, Washington County receives approximately 33.7 inches of rainfall annually with predominantly silt loam soil. Summer highs average 87ยฐF, providing good warmth for Pac Choi during the growing season.

Washington County, IL (Zone 6a) Moderate season
194 days
Last Spring Frost April 9
194 growing days
First Fall Frost October 20

Washington County Soil Profile

Soil Type

Silt Loam

Soil pH

5.9-7.2

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (121 days to spare)
Start indoors: Feb 28 Transplant: Apr 4 🍅 Harvest: May 16 – Jun 13
Recommended (50%) ✓ Fits season (124 days to spare)
Start indoors: Mar 5 Transplant: Apr 9 🍅 Harvest: May 21 – Jun 18
Safe Start (90%) ✓ Fits season (124 days to spare)
Start indoors: Mar 15 Transplant: Apr 19 🍅 Harvest: May 31 – Jun 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 Washington County

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

Soil pH

Your soil pH (5.9โ€“7.2) overlaps with Pac Choi's range (6.0โ€“7.5), though not a perfect match.

Soil Texture

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

Organic Matter

Organic matter is moderate (3.9%). 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

5
successive plantings in your 194-day season

Sow every 4.6 weeks. Last sowing by Aug 26 to harvest before frost.

For a dedicated fall crop, sow by Aug 11.

Plant Water Budget

Plant needs
1.5″/week
Rainfall provides
0.7″/week
You supply
0.8″/week
Watering frequency 2-3 times/week
Season total 1,330 gal / 100 sq ft

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€” 1.3" 0" โ„๏ธ Dormant
Feb โ€” 1.5" 0" โ„๏ธ Dormant
Mar โ€” 2.4" 0" โ„๏ธ Dormant
Apr 6.5" 3.7" 2.8" ๐Ÿ’ง Light watering
May 6.5" 3.4" 3.1" ๐Ÿ’ง Light watering
Jun 6.5" 4.3" 2.2" ๐Ÿ’ง Light watering
Jul 6.5" 3.9" 2.6" ๐Ÿ’ง Light watering
Aug 6.5" 3.8" 2.7" ๐Ÿ’ง Light watering
Sep 6.5" 2.8" 3.7" ๐Ÿšฟ Regular watering
Oct 6.5" 2.5" 4" ๐Ÿšฟ Regular watering
Nov โ€” 2.2" 0" โ„๏ธ Dormant
Dec โ€” 1.8" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Aprโ€“Oct in Washington 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 ~724 GDD — county provides 2,958 GDD Excellent fit

Pac Choi Planting Timeline โ€” Washington County, IL

Pac Choi Planting Calendar

Activity When Date Range
Start Indoors March 5 Mar 5 โ€“ Mar 19
Transplant Outdoors April 9 Apr 9 โ€“ Apr 23
Direct Sow March 26 Mar 26 โ€“ Apr 16
Harvest May 21 May 21 โ€“ Jun 18
Fall Sowing August 11 Aug 11 โ€“ Aug 25

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

Month-by-Month Timeline

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

194 days in Washington County

Growing Tips for Pac Choi in Washington County

Direct sow Pac Choi outdoors after April 09 in Washington County when soil has warmed and frost danger has passed.

Your generous 194.0-day season in Washington County allows multiple plantings of Pac Choi. Sow every 20.0 days for continuous harvest.

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 Washington County, IL?

Washington County is in Zone 6a with an average last frost of April 9. Plan your Pac Choi planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Washington County, IL?

Washington County, Illinois is in USDA Hardiness Zone 6a. The average last spring frost is April 9 and first fall frost is October 20.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Washington County gardeners in Zone 6a 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 Washington County, IL. Local conditions may vary. Last updated: April 2026.