When to Plant Napa Cabbage in Knox County, TX
May to-do list for Knox County, Texas
We've pulled the most time-sensitive tasks for Knox County, Texas this May and put them front and centre. Tackle them in order.
-
It's harvest week for napa cabbage
This is the payoff month. Bring a basket, bring a friend, and get into the beds.
Looking ahead to June
- First harvests: napa cabbage
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.
Knox County, Texas is in USDA Zone 8a. The average last spring frost is March 24 and the first fall frost is November 12, giving you a growing season of approximately 233 days.
At an elevation of 1,847 feet, Knox County receives approximately 51.2 inches of rainfall annually with predominantly loam soil. Summer highs average 93°F, 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.
Knox County Soil Profile
Soil Type
Loam
Soil pH
6.4-7.2
Drainage
Well Drained
Plant Planting Risk Windows
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 Knox County
How your county's soil matches Napa Cabbage's growing requirements.
Soil pH
Your soil pH (6.4–7.2) is within Napa Cabbage's preferred range (6.0–7.5).
Soil Texture
The loam soil in Knox County is excellent for Napa Cabbage — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is low (1.9%). Add 2-3 inches of compost before planting Napa Cabbage.
How to Plant Napa Cabbage
Fall planting: Sow 10 weeks before your first frost date for a fall harvest.
Succession Planting Napa Cabbage
Sow every 6.3 weeks. Last sowing by Aug 29 to harvest before frost.
For a dedicated fall crop, sow by Sep 03.
Plant Water Budget
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 | — | 1.3" | 0" | ❄️ Dormant |
| Feb | — | 2.1" | 0" | ❄️ Dormant |
| Mar | 6.5" | 3.2" | 3.3" | 🚿 Regular watering |
| Apr | 6.5" | 6.4" | 0.1" | 💧 Light watering |
| May | 6.5" | 6.7" | 0" | ✅ Rainfall sufficient |
| Jun | 6.5" | 7.3" | 0" | ✅ Rainfall sufficient |
| Jul | 6.5" | 6.5" | 0" | ✅ Rainfall sufficient |
| Aug | 6.5" | 5.9" | 0.6" | 💧 Light watering |
| Sep | 6.5" | 5.4" | 1.1" | 💧 Light watering |
| Oct | 6.5" | 3.3" | 3.2" | 💧 Light watering |
| Nov | 6.5" | 1.8" | 4.7" | 🚿 Regular watering |
| Dec | — | 1.3" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Mar–Nov in Knox 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 Planting Timeline — Knox County, TX
Napa Cabbage Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | February 17 | Feb 17 – Mar 3 |
| Transplant Outdoors | March 24 | Mar 24 – Apr 7 |
| Direct Sow | March 10 | Mar 10 – Mar 31 |
| Harvest | May 19 | May 19 – Jun 23 |
| Fall Sowing | September 3 | Sep 3 – Sep 17 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | Start Indoors |
| March | Start Indoors Transplant Outdoors Direct Sow |
| April | Transplant Outdoors |
| May | Harvest |
| June | Harvest |
| July | — |
| August | — |
| September | Fall Sowing |
| October | — |
| November | — |
| December | — |
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: ideal
🗺️ USDA Zone
Zone 8a
📆 Growing Season
233 days in Knox County
Growing Tips for Napa Cabbage in Knox County
Direct sow Napa Cabbage outdoors after March 24 in Knox 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
Check more plant combinations with our Companion Planting Checker →
Napa Cabbage in Other Locations
Frequently Asked Questions
When should I plant Napa Cabbage in Knox County, TX?
Knox County is in Zone 8a with an average last frost of March 24. Plan your Napa Cabbage planting based on this frost date — see the calendar above for exact timing.
What planting zone is Knox County, TX?
Knox County, Texas is in USDA Hardiness Zone 8a. The average last spring frost is March 24 and first fall frost is November 12.
Your Knox County Garden Planner — Free
A 24-page printable planner built for Knox 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.