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When to Plant Napa Cabbage in Lamar County, TX

Lamar County, Texas Zone 8a May

May in Lamar County, Texas — your action list

May is a pivotal month for Lamar County, Texas gardens. Focus on these tasks first and you'll set up the rest of the season for success.

Avg. last frost March 15
Avg. first frost November 15
Soil temp (4") 69°F
Watering Low
Pest pressure Moderate
Daylight 13.7 hrs
  1. It's harvest week for napa cabbage

    Check every 1–2 days. Many of these get tough or go to seed if you wait too long.

Before June arrives, get these ready
  • First harvests: napa cabbage

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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.

Lamar County, Texas is in USDA Zone 8a. The average last spring frost is March 15 and the first fall frost is November 15, giving you a growing season of approximately 245 days.

At an elevation of 95 feet, Lamar County receives approximately 59.8 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 91°F, providing good warmth for Napa Cabbage during the growing season. Sandy soil warms quickly in spring — great for early planting — but Napa Cabbage will need more frequent watering and organic matter to retain nutrients. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Napa Cabbage root diseases.

Lamar County, TX (Zone 8a) Long season
245 days
Last Spring Frost March 15
245 growing days
First Fall Frost November 15
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Lamar County Soil Profile

Soil Type

Sandy Loam

Soil pH

5.8-6.8

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (150 days to spare)
Start indoors: Jan 31 Transplant: Mar 7 🍅 Harvest: May 2 – Jun 6
Recommended (50%) ✓ Fits season (154 days to spare)
Start indoors: Feb 8 Transplant: Mar 15 🍅 Harvest: May 10 – Jun 14
Safe Start (90%) ✓ Fits season (144 days to spare)
Start indoors: Mar 5 Transplant: Apr 9 🍅 Harvest: Jun 4 – Jul 9

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 Lamar County

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

Soil pH

Your soil pH (5.8–6.8) overlaps with Napa Cabbage's range (6.0–7.5), though not a perfect match.

Soil Texture

Sandy soil in Lamar County warms quickly in spring but drains fast. Napa Cabbage will need more frequent watering and regular compost additions to retain nutrients.

Organic Matter

Organic matter is low (1.9%). Add 2-3 inches of compost before planting 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

5
successive plantings in your 245-day season

Sow every 6.3 weeks. Last sowing by Sep 01 to harvest before frost.

For a dedicated fall crop, sow by Sep 06.

Plant Water Budget

Plant needs
1.5″/week
Rainfall provides
1.0″/week
You supply
0.5″/week
Watering frequency 1-2 times/week
Season total 1,035 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 1.7" 0" ❄️ Dormant
Feb 2.1" 0" ❄️ Dormant
Mar 6.5" 3.5" 3" 💧 Light watering
Apr 6.5" 6.8" 0" ✅ Rainfall sufficient
May 6.5" 8.8" 0" ✅ Rainfall sufficient
Jun 6.5" 9.7" 0" ✅ Rainfall sufficient
Jul 6.5" 8" 0" ✅ Rainfall sufficient
Aug 6.5" 7.1" 0" ✅ Rainfall sufficient
Sep 6.5" 5.3" 1.2" 💧 Light watering
Oct 6.5" 3.4" 3.1" 💧 Light watering
Nov 6.5" 2.2" 4.3" 🚿 Regular watering
Dec 1.4" 0" ❄️ Dormant

Water needs are for active growing months only (Mar–Nov in Lamar County). Supplement amounts are based on average rainfall — 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" — 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.

Napa Cabbage needs ~1,186 GDD — county provides 4,471 GDD Excellent fit

Napa Cabbage Planting Timeline — Lamar County, TX

Napa Cabbage Planting Calendar

Activity When Date Range
Start Indoors February 8 Feb 8 – Feb 22
Transplant Outdoors March 15 Mar 15 – Mar 29
Direct Sow March 1 Mar 1 – Mar 22
Harvest May 10 May 10 – Jun 14
Fall Sowing September 6 Sep 6 – Sep 20

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

Month-by-Month Timeline

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

☀️ Sun

Partial Shade (3-6 hours)

💧 Water

1.5"/week · 1-2 times/week

📅 Days to Maturity

55–75 days

🧪 Soil pH

Needs 6–7.5 · Your soil: acceptable

🗺️ USDA Zone

Zone 8a

📆 Growing Season

245 days in Lamar County

Growing Tips for Napa Cabbage in Lamar County

Direct sow Napa Cabbage outdoors after March 15 in Lamar County when soil has warmed and frost danger has passed.

Sandy soil in Lamar County dries quickly — mulch Napa Cabbage with 2-3 inches of straw and water deeply 2-3 times per week rather than lightly every day.

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 Lamar County, TX?

Lamar County is in Zone 8a with an average last frost of March 15. Plan your Napa Cabbage planting based on this frost date — see the calendar above for exact timing.

What planting zone is Lamar County, TX?

Lamar County, Texas is in USDA Hardiness Zone 8a. The average last spring frost is March 15 and first fall frost is November 15.

🌱

Your Lamar County Garden Planner — Free

A 24-page printable planner built for Lamar County (Zone 8a). 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 Lamar County, TX. Local conditions may vary. Last updated: May 2026.

Sources & credits

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