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When to Plant Napa Cabbage in Saline County, IL

Napa cabbage forms tall, barrel-shaped heads with tender, crinkled leaves and a mild, slightly sweet flavor. It is the primary cabbage used for kimchi.

Saline County, Illinois is in USDA Zone 6b. The average last spring frost is April 8 and the first fall frost is October 24, giving you a growing season of approximately 199 days.

At an elevation of 748 feet, Saline County receives approximately 41.1 inches of rainfall annually with predominantly silt loam soil. Summer highs average 88ยฐF, providing good warmth for Napa Cabbage during the growing season.

Saline County, IL (Zone 6b) Moderate season
199 days
Last Spring Frost April 8
199 growing days
First Fall Frost October 24

Saline County Soil Profile

Soil Type

Silt Loam

Soil pH

6-6.7

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (105 days to spare)
Start indoors: Feb 28 Transplant: Apr 4 🍅 Harvest: May 30 – Jul 4
Recommended (50%) ✓ Fits season (108 days to spare)
Start indoors: Mar 4 Transplant: Apr 8 🍅 Harvest: Jun 3 – Jul 8
Safe Start (90%) ✓ Fits season (115 days to spare)
Start indoors: Mar 17 Transplant: Apr 21 🍅 Harvest: Jun 16 – Jul 21

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 Saline County

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

Soil pH

Your soil pH (6.0โ€“6.7) is within Napa Cabbage's preferred range (6.0โ€“7.5).

Soil Texture

The silt loam soil in Saline County is excellent for Napa Cabbage โ€” good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is moderate (3.9%). Annual compost additions will help Napa Cabbage.

How to Plant Napa Cabbage

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 Napa Cabbage

4
successive plantings in your 199-day season

Sow every 6.3 weeks. Last sowing by Aug 10 to harvest before frost.

For a dedicated fall crop, sow by Aug 15.

Plant Water Budget

Plant needs
1.5″/week
Rainfall provides
0.9″/week
You supply
0.6″/week
Watering frequency 1-2 times/week
Season total 1,120 gal / 100 sq ft

Monthly Watering Guide for Napa Cabbage

Napa 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 Napa Cabbage Needs Rainfall You Supplement Action
Jan โ€” 1.7" 0" โ„๏ธ Dormant
Feb โ€” 2" 0" โ„๏ธ Dormant
Mar โ€” 3.2" 0" โ„๏ธ Dormant
Apr 6.5" 4.3" 2.2" ๐Ÿ’ง Light watering
May 6.5" 4.7" 1.8" ๐Ÿ’ง Light watering
Jun 6.5" 4.6" 1.9" ๐Ÿ’ง Light watering
Jul 6.5" 4.8" 1.7" ๐Ÿ’ง Light watering
Aug 6.5" 4.5" 2" ๐Ÿ’ง Light watering
Sep 6.5" 3.2" 3.3" ๐Ÿšฟ Regular watering
Oct 6.5" 2.9" 3.6" ๐Ÿšฟ Regular watering
Nov โ€” 2.9" 0" โ„๏ธ Dormant
Dec โ€” 2.2" 0" โ„๏ธ Dormant

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

Napa 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" 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.

Napa Cabbage needs ~1,040 GDD — county provides 3,184 GDD Excellent fit

Napa Cabbage Planting Timeline โ€” Saline County, IL

Napa Cabbage Planting Calendar

Activity When Date Range
Start Indoors March 4 Mar 4 โ€“ Mar 18
Transplant Outdoors April 8 Apr 8 โ€“ Apr 22
Direct Sow March 25 Mar 25 โ€“ Apr 15
Harvest June 3 Jun 3 โ€“ Jul 8
Fall Sowing August 15 Aug 15 โ€“ Aug 29

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 โ€”
June Harvest
July Harvest
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 1-2 times/week

๐Ÿ“… Days to Maturity

55โ€“75 days

๐Ÿงช Soil pH

Needs 6โ€“7.5 ยท Your soil: ideal

๐Ÿ—บ๏ธ USDA Zone

Zone 6b

๐Ÿ“† Growing Season

199 days in Saline County

Growing Tips for Napa Cabbage in Saline County

Direct sow Napa Cabbage outdoors after April 08 in Saline County when soil has warmed and frost danger has passed.

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

General growing tips

Best grown as a fall crop. Direct sow in late summer, 60-70 days before first frost. Keep soil evenly moist. Bolt-resistant varieties are available for spring planting.

Companion Planting

Good Companions

Avoid Planting Near

  • Strawberries

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Napa Cabbage in Saline County, IL?

Saline County is in Zone 6b with an average last frost of April 8. Plan your Napa Cabbage planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Saline County, IL?

Saline County, Illinois is in USDA Hardiness Zone 6b. The average last spring frost is April 8 and first fall frost is October 24.

๐ŸŒฑ

Plan Your Garden with Confidence

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

Get Your Free Garden Planner →

Free download. Plan your entire garden season in minutes.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Saline County, IL. Local conditions may vary. Last updated: April 2026.