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When to Plant Cabbage in Onslow County, NC

Cabbage is a versatile cool-season crop that forms dense, leafy heads in green, red, or savoy varieties. It is a staple for coleslaw, sauerkraut, and many global cuisines.

Onslow County, North Carolina is in USDA Zone 8a. The average last spring frost is March 21 and the first fall frost is November 18, giving you a growing season of approximately 242 days.

At an elevation of 541 feet, Onslow County receives approximately 46.8 inches of rainfall annually with predominantly clay loam soil. Summer highs average 90ยฐF, providing good warmth for Cabbage during the growing season. Clay soil retains moisture well for Cabbage, but amend with compost to improve drainage and prevent root rot.

Onslow County, NC (Zone 8a) Long season
242 days
Last Spring Frost March 21
242 growing days
First Fall Frost November 18

Onslow County Soil Profile

Soil Type

Clay Loam

Soil pH

5.5-6.2

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (126 days to spare)
Start indoors: Feb 4 Transplant: Mar 11 🍅 Harvest: May 13 – Jul 8
Recommended (50%) ✓ Fits season (123 days to spare)
Start indoors: Feb 14 Transplant: Mar 21 🍅 Harvest: May 23 – Jul 18
Safe Start (90%) ✓ Fits season (119 days to spare)
Start indoors: Mar 4 Transplant: Apr 8 🍅 Harvest: Jun 10 – Aug 5

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 Onslow County

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

Soil pH

Your soil pH (5.5โ€“6.2) is more acidic than Cabbage prefers (6.0โ€“7.5). Add garden lime to raise pH.

Soil Texture

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

Organic Matter

Organic matter is moderate (2.3%). Annual compost additions will help Cabbage.

How to Plant 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 Cabbage

4
successive plantings in your 242-day season

Sow every 6.9 weeks. Last sowing by Aug 10 to harvest before frost.

For a dedicated fall crop, sow by Sep 09.

Plant Water Budget

Plant needs
0.9″/week
Rainfall provides
0.8″/week
You supply
0.1″/week
Watering frequency Only during dry spells
Season total 189 gal / 100 sq ft

Monthly Watering Guide for Cabbage

Cabbage needs approximately 0.9 inches of water per week (3.9" per month). Here's how your county's rainfall compares month by month.

Month Cabbage Needs Rainfall You Supplement Action
Jan โ€” 4" 0" โ„๏ธ Dormant
Feb โ€” 3.9" 0" โ„๏ธ Dormant
Mar 3.9" 4.2" 0" โœ… Rainfall sufficient
Apr 3.9" 3.1" 0.8" ๐Ÿ’ง Light watering
May 3.9" 4" 0" โœ… Rainfall sufficient
Jun 3.9" 4.2" 0" โœ… Rainfall sufficient
Jul 3.9" 4.3" 0" โœ… Rainfall sufficient
Aug 3.9" 4.1" 0" โœ… Rainfall sufficient
Sep 3.9" 3.8" 0.1" ๐Ÿ’ง Light watering
Oct 3.9" 3.1" 0.8" ๐Ÿ’ง Light watering
Nov 3.9" 4" 0" โœ… Rainfall sufficient
Dec โ€” 4" 0" โ„๏ธ Dormant

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

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.

Cabbage needs ~1,400 GDD — county provides 4,235 GDD Excellent fit

Cabbage Planting Timeline โ€” Onslow County, NC

Cabbage Planting Calendar

Activity When Date Range
Start Indoors February 14 Feb 14 โ€“ Feb 28
Transplant Outdoors March 21 Mar 21 โ€“ Apr 4
Direct Sow March 7 Mar 7 โ€“ Mar 28
Harvest May 23 May 23 โ€“ Jul 18
Fall Sowing September 9 Sep 9 โ€“ Sep 23

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

Month-by-Month Timeline

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

Growing Conditions

โ˜€๏ธ Sun

Full Sun (6-8+ hours)

๐Ÿ’ง Water

0.9"/week ยท Only during dry spells

๐Ÿ“… Days to Maturity

60โ€“100 days

๐Ÿงช Soil pH

Needs 6โ€“7.5 ยท Your soil: too_acidic

๐Ÿ—บ๏ธ USDA Zone

Zone 8a

๐Ÿ“† Growing Season

242 days in Onslow County

Growing Tips for Cabbage in Onslow County

Direct sow Cabbage outdoors after March 21 in Onslow County when soil has warmed and frost danger has passed.

With Onslow County's clay soil (30% clay), work in 3-4 inches of compost before planting Cabbage. Avoid tilling when soil is wet to prevent compaction.

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

General growing tips

Start seeds indoors 4-6 weeks before last frost. Space plants 18-24 inches apart. Keep soil evenly moist to prevent heads from splitting.

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 Cabbage in Onslow County, NC?

Onslow County is in Zone 8a with an average last frost of March 21. Plan your Cabbage planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Onslow County, NC?

Onslow County, North Carolina is in USDA Hardiness Zone 8a. The average last spring frost is March 21 and first fall frost is November 18.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Onslow County gardeners in Zone 8a 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 Onslow County, NC. Local conditions may vary. Last updated: April 2026.