When to Plant Napa Cabbage in Sumner County, KS
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.
Sumner County, Kansas is in USDA Zone 6b. The average last spring frost is April 11 and the first fall frost is October 26, giving you a growing season of approximately 198 days.
At an elevation of 637 feet, Sumner County receives approximately 29 inches of rainfall annually with predominantly loam soil. Summer highs average 85°F, providing good warmth for Napa Cabbage during the growing season.
Sumner County Soil Profile
Soil Type
Loam
Soil pH
6.4-7.8
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 Sumner County
How your county's soil matches Napa Cabbage's growing requirements.
Soil pH
Your soil pH (6.4–7.8) overlaps with Napa Cabbage's range (6.0–7.5), though not a perfect match.
Soil Texture
The loam soil in Sumner County is excellent for Napa Cabbage — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (3.6%). Annual compost additions will help 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 12 to harvest before frost.
For a dedicated fall crop, sow by Aug 17.
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 | — | 0.7" | 0" | ❄️ Dormant |
| Feb | — | 1.1" | 0" | ❄️ Dormant |
| Mar | — | 1.7" | 0" | ❄️ Dormant |
| Apr | 6.5" | 3" | 3.5" | 🚿 Regular watering |
| May | 6.5" | 4.4" | 2.1" | 💧 Light watering |
| Jun | 6.5" | 4.2" | 2.3" | 💧 Light watering |
| Jul | 6.5" | 3.4" | 3.1" | 💧 Light watering |
| Aug | 6.5" | 4" | 2.5" | 💧 Light watering |
| Sep | 6.5" | 3" | 3.5" | 🚿 Regular watering |
| Oct | 6.5" | 1.7" | 4.8" | 🚿 Regular watering |
| Nov | — | 1.1" | 0" | ❄️ Dormant |
| Dec | — | 0.7" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Sumner 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 — Sumner County, KS
Napa Cabbage Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 7 | Mar 7 – Mar 21 |
| Transplant Outdoors | April 11 | Apr 11 – Apr 25 |
| Direct Sow | March 28 | Mar 28 – Apr 18 |
| Harvest | June 6 | Jun 6 – Jul 11 |
| Fall Sowing | August 17 | Aug 17 – Aug 31 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors Direct Sow |
| April | Transplant Outdoors Direct Sow |
| May | — |
| June | Harvest |
| July | Harvest |
| August | Fall Sowing |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Partial Shade (3-6 hours)
💧 Water
1.5"/week · 2-3 times/week
📅 Days to Maturity
55–75 days
🧪 Soil pH
Needs 6–7.5 · Your soil: acceptable
🗺️ USDA Zone
Zone 6b
📆 Growing Season
198 days in Sumner County
Growing Tips for Napa Cabbage in Sumner County
Direct sow Napa Cabbage outdoors after April 11 in Sumner 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
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Napa Cabbage in Other Locations
Frequently Asked Questions
When should I plant Napa Cabbage in Sumner County, KS?
Sumner County is in Zone 6b with an average last frost of April 11. Plan your Napa Cabbage planting based on this frost date — see the calendar above for exact timing.
What planting zone is Sumner County, KS?
Sumner County, Kansas is in USDA Hardiness Zone 6b. The average last spring frost is April 11 and first fall frost is October 26.
Plan Your Garden with Confidence
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