When to Plant Napa Cabbage in Robertson County, TX
May in Robertson County, Texas — your action list
Your Robertson County, Texas garden is entering a new phase. Here's what's on the schedule for May and why each task matters now.
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Pick napa cabbage
If you can't use it all right away, check the food-preservation section of your planner.
June prep starts now
- 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.
Robertson County, Texas is in USDA Zone 9a. The average last spring frost is March 7 and the first fall frost is November 16, giving you a growing season of approximately 254 days.
At an elevation of 85 feet, Robertson County receives approximately 61.1 inches of rainfall annually with predominantly clay soil. Summer highs average 93°F, providing good warmth for Napa Cabbage during the growing season. Clay soil retains moisture well for Napa Cabbage, but amend with compost to improve drainage and prevent root rot. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Napa Cabbage root diseases.
Robertson County Soil Profile
Soil Type
Clay
Soil pH
6.8-8
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 Robertson County
How your county's soil matches Napa Cabbage's growing requirements.
Soil pH
Your soil pH (6.8–8.0) overlaps with Napa Cabbage's range (6.0–7.5), though not a perfect match.
Soil Texture
Heavy clay soil (45% clay) in Robertson County compacts easily and drains slowly. Amend with compost and avoid working soil when wet.
Organic Matter
Organic matter is moderate (3.4%). Annual compost additions will help Napa Cabbage.
How to Plant Napa Cabbage
Fall planting: Sow 8 weeks before your first frost date for a fall harvest.
Succession Planting Napa Cabbage
Sow every 6.3 weeks. Last sowing by Sep 02 to harvest before frost.
For a dedicated fall crop, sow by Sep 21.
Plant Water Budget
Water stress score is 6/10 — 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 | — | 1.4" | 0" | ❄️ Dormant |
| Feb | — | 2.2" | 0" | ❄️ Dormant |
| Mar | 6.5" | 4.3" | 2.2" | 💧 Light watering |
| Apr | 6.5" | 5.6" | 0.9" | 💧 Light watering |
| May | 6.5" | 10" | 0" | ✅ Rainfall sufficient |
| Jun | 6.5" | 8.4" | 0" | ✅ Rainfall sufficient |
| Jul | 6.5" | 8.3" | 0" | ✅ Rainfall sufficient |
| Aug | 6.5" | 8.2" | 0" | ✅ Rainfall sufficient |
| Sep | 6.5" | 5.2" | 1.3" | 💧 Light watering |
| Oct | 6.5" | 3.7" | 2.8" | 💧 Light watering |
| Nov | 6.5" | 2.3" | 4.2" | 🚿 Regular watering |
| Dec | — | 1.6" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Mar–Nov in Robertson 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 — Robertson County, TX
Napa Cabbage Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | February 7 | Feb 7 – Feb 21 |
| Transplant Outdoors | March 7 | Mar 7 – Mar 21 |
| Direct Sow | February 14 | Feb 14 – Mar 7 |
| Harvest | May 2 | May 2 – Jun 6 |
| Fall Sowing | September 21 | Sep 21 – Oct 5 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | Start Indoors Direct Sow |
| March | Transplant Outdoors Direct Sow |
| April | — |
| May | Harvest |
| June | Harvest |
| July | — |
| August | — |
| September | Fall Sowing |
| October | Fall Sowing |
| 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: acceptable
🗺️ USDA Zone
Zone 9a
📆 Growing Season
254 days in Robertson County
Growing Tips for Napa Cabbage in Robertson County
Direct sow Napa Cabbage outdoors after March 07 in Robertson County when soil has warmed and frost danger has passed.
With Robertson County's clay soil (45% clay), work in 3-4 inches of compost before planting Napa Cabbage. Avoid tilling when soil is wet to prevent compaction.
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 Robertson County, TX?
Robertson County is in Zone 9a with an average last frost of March 7. Plan your Napa Cabbage planting based on this frost date — see the calendar above for exact timing.
What planting zone is Robertson County, TX?
Robertson County, Texas is in USDA Hardiness Zone 9a. The average last spring frost is March 7 and first fall frost is November 16.
Your Robertson County Garden Planner — Free
A 24-page printable planner built for Robertson County (Zone 9a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.