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When to Plant Napa Cabbage in Oldham County, KY

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.

Oldham County, Kentucky is in USDA Zone 6b. The average last spring frost is April 10 and the first fall frost is October 22, giving you a growing season of approximately 195 days.

At an elevation of 3,065 feet, Oldham County receives approximately 53.2 inches of rainfall annually with predominantly silt loam soil. Summer highs average 86ยฐF, providing good warmth for Napa Cabbage during the growing season. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Napa Cabbage root diseases.

Oldham County, KY (Zone 6b) Moderate season
195 days
Last Spring Frost April 10
195 growing days
First Fall Frost October 22

Oldham County Soil Profile

Soil Type

Silt Loam

Soil pH

5.2-6.5

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 (104 days to spare)
Start indoors: Mar 6 Transplant: Apr 10 🍅 Harvest: Jun 5 – Jul 10
Safe Start (90%) ✓ Fits season (101 days to spare)
Start indoors: Mar 26 Transplant: Apr 30 🍅 Harvest: Jun 25 – Jul 30

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 Oldham County

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

Soil pH

Your soil pH (5.2โ€“6.5) is more acidic than Napa Cabbage prefers (6.0โ€“7.5). Add garden lime to raise pH.

Soil Texture

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

Organic Matter

Organic matter is moderate (2.8%). 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 195-day season

Sow every 6.3 weeks. Last sowing by Aug 08 to harvest before frost.

For a dedicated fall crop, sow by Aug 13.

Plant Water Budget

Plant needs
1.5″/week
Rainfall provides
1.2″/week
You supply
0.4″/week
Watering frequency 1-2 times/week
Season total 738 gal / 100 sq ft
Drought risk

Water stress score is 6/10 โ€” consider drought-tolerant varieties and mulching

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€” 3.7" 0" โ„๏ธ Dormant
Feb โ€” 4" 0" โ„๏ธ Dormant
Mar โ€” 5.4" 0" โ„๏ธ Dormant
Apr 6.5" 3.9" 2.6" ๐Ÿ’ง Light watering
May 6.5" 4.5" 2" ๐Ÿ’ง Light watering
Jun 6.5" 5.3" 1.2" ๐Ÿ’ง Light watering
Jul 6.5" 5.6" 0.9" ๐Ÿ’ง Light watering
Aug 6.5" 5.4" 1.1" ๐Ÿ’ง Light watering
Sep 6.5" 3.7" 2.8" ๐Ÿ’ง Light watering
Oct 6.5" 3.7" 2.8" ๐Ÿ’ง Light watering
Nov โ€” 3.4" 0" โ„๏ธ Dormant
Dec โ€” 4.5" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Aprโ€“Oct in Oldham 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 ~942 GDD — county provides 2,827 GDD Excellent fit

Napa Cabbage Planting Timeline โ€” Oldham County, KY

Napa Cabbage Planting Calendar

Activity When Date Range
Start Indoors March 6 Mar 6 โ€“ Mar 20
Transplant Outdoors April 10 Apr 10 โ€“ Apr 24
Direct Sow March 27 Mar 27 โ€“ Apr 17
Harvest June 5 Jun 5 โ€“ Jul 10
Fall Sowing August 13 Aug 13 โ€“ Aug 27

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: too_acidic

๐Ÿ—บ๏ธ USDA Zone

Zone 6b

๐Ÿ“† Growing Season

195 days in Oldham County

Growing Tips for Napa Cabbage in Oldham County

Direct sow Napa Cabbage outdoors after April 10 in Oldham 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 Oldham County, KY?

Oldham County is in Zone 6b with an average last frost of April 10. Plan your Napa Cabbage planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Oldham County, KY?

Oldham County, Kentucky is in USDA Hardiness Zone 6b. The average last spring frost is April 10 and first fall frost is October 22.

๐ŸŒฑ

Plan Your Garden with Confidence

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