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When to Plant Pac Choi in Iroquois County, IL

Iroquois County, Illinois Zone 5a April

Your April planting checklist for Iroquois County, Illinois

Your Iroquois County, Illinois garden is entering a new phase. Here's what's on the schedule for April and why each task matters now.

Avg. last frost April 18
Avg. first frost October 13
Soil temp (4") 43°F
Watering Moderate
Pest pressure Low
Daylight 13.1 hrs
  1. Plant out pac choi

    Pinch off the lowest leaves on each seedling before you plant — it reduces water loss while the roots catch up.

  2. Put pac choi seeds straight in the ground

    Succession planting is the secret here. Put in a row now, another in 2 weeks, a third in 4.

To set up a strong May, finish these tasks
  • Starting indoors: pac choi
  • First harvests: pac choi

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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.

Iroquois County, Illinois is in USDA Zone 5a. The average last spring frost is April 18 and the first fall frost is October 13, giving you a growing season of approximately 178 days.

At an elevation of 1,345 feet, Iroquois County receives approximately 30 inches of rainfall annually with predominantly silt loam soil. Summer highs average 85°F, providing good warmth for Pac Choi during the growing season.

Iroquois County, IL (Zone 5a) Moderate season
178 days
Last Spring Frost April 18
178 growing days
First Fall Frost October 13
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Iroquois County Soil Profile

Soil Type

Silt Loam

Soil pH

5.9-6.7

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (108 days to spare)
Start indoors: Mar 9 Transplant: Apr 13 🍅 Harvest: May 25 – Jun 22
Recommended (50%) ✓ Fits season (108 days to spare)
Start indoors: Mar 14 Transplant: Apr 18 🍅 Harvest: May 30 – Jun 27
Safe Start (90%) ✓ Fits season (106 days to spare)
Start indoors: Apr 1 Transplant: May 6 🍅 Harvest: Jun 17 – Jul 15

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 Iroquois County

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

Soil pH

Your soil pH (5.9–6.7) overlaps with Pac Choi's range (6.0–7.5), though not a perfect match.

Soil Texture

The silt loam soil in Iroquois County is excellent for Pac Choi — 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 excellent (4.5%) — Pac Choi will thrive.

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 178-day season

Sow every 4.6 weeks. Last sowing by Aug 19 to harvest before frost.

For a dedicated fall crop, sow by Aug 04.

Plant Water Budget

Plant needs
1.5″/week
Rainfall provides
0.7″/week
You supply
1.5″/week
Watering frequency 2-3 times/week
Season total 2,361 gal / 100 sq ft
Drought risk

Water stress score is 6/10 — 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 1.3" 0" ❄️ Dormant
Feb 1.4" 0" ❄️ Dormant
Mar 1.9" 0" ❄️ Dormant
Apr 6.5" 2.8" 3.7" 🚿 Regular watering
May 6.5" 3.8" 2.7" 💧 Light watering
Jun 6.5" 3.6" 2.9" 💧 Light watering
Jul 6.5" 3" 3.5" 🚿 Regular watering
Aug 6.5" 2.9" 3.6" 🚿 Regular watering
Sep 6.5" 3.2" 3.3" 🚿 Regular watering
Oct 6.5" 2.5" 4" 🚿 Regular watering
Nov 2" 0" ❄️ Dormant
Dec 1.6" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Iroquois County). Supplement amounts are based on average rainfall — 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" — 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.

Pac Choi needs ~653 GDD — county provides 2,447 GDD Excellent fit

Pac Choi Planting Timeline — Iroquois County, IL

Pac Choi Planting Calendar

Activity When Date Range
Start Indoors March 14 Mar 14 – Mar 28
Transplant Outdoors April 18 Apr 18 – May 2
Direct Sow April 4 Apr 4 – Apr 25
Harvest May 30 May 30 – Jun 27
Fall Sowing August 4 Aug 4 – Aug 18

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

Month-by-Month Timeline

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

☀️ Sun

Partial Shade (3-6 hours)

💧 Water

1.5"/week · 2-3 times/week

📅 Days to Maturity

40–55 days

🧪 Soil pH

Needs 6–7.5 · Your soil: acceptable

🗺️ USDA Zone

Zone 5a

📆 Growing Season

178 days in Iroquois County

Growing Tips for Pac Choi in Iroquois County

Direct sow Pac Choi outdoors after April 18 in Iroquois County when soil has warmed and frost danger has passed.

Your generous 178.0-day season in Iroquois 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 Iroquois County, IL?

Iroquois County is in Zone 5a with an average last frost of April 18. Plan your Pac Choi planting based on this frost date — see the calendar above for exact timing.

What planting zone is Iroquois County, IL?

Iroquois County, Illinois is in USDA Hardiness Zone 5a. The average last spring frost is April 18 and first fall frost is October 13.

🌱

Your Iroquois County Garden Planner — Free

A 24-page printable planner built for Iroquois County (Zone 5a). 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 Iroquois County, IL. Local conditions may vary. Last updated: April 2026.

Sources & credits

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