When to plant Napa Cabbage in Mitchell County, IA
Mitchell County gardeners should plant Napa Cabbage between April 19 and May 10 in spring. With Mitchell County's Zone 5a climate (last frost May 3), Napa Cabbage needs 55–75 days to mature — plant by July 24 for a full harvest. A second sowing from July 29 to August 12 extends the harvest into fall.
When to Plant Napa Cabbage in Mitchell County, IA
Your July planting checklist for Mitchell County, Iowa
July is a pivotal month for Mitchell County, Iowa gardens. Focus on these tasks first and you'll set up the rest of the season for success.
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.
Mitchell County, Iowa is in USDA Zone 5a. The average last spring frost is May 3 and the first fall frost is October 7, giving you a growing season of approximately 157 days.
At an elevation of 506 feet, Mitchell County receives approximately 36.1 inches of rainfall annually with predominantly silt loam soil. Summer highs average 84°F, so choose short-season varieties of Napa Cabbage to ensure they mature before fall.
Mitchell County Soil Profile
Soil Type
Silt Loam
Soil pH
5.9-7.3
Drainage
Well Drained
Napa Cabbage 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 Mitchell County
How your county's soil matches Napa Cabbage's growing requirements.
Soil pH
Your soil pH (5.9–7.3) overlaps with Napa Cabbage's range (6.0–7.5), though not a perfect match.
Soil Texture
The silt loam soil in Mitchell County is excellent for Napa Cabbage — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is excellent (5.1%) — Napa Cabbage will thrive.
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 Jul 24 to harvest before frost.
For a dedicated fall crop, sow by Jul 29.
Napa Cabbage 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 | — | 1.4" | 0" | ❄️ Dormant |
| Feb | — | 1.5" | 0" | ❄️ Dormant |
| Mar | — | 2.7" | 0" | ❄️ Dormant |
| Apr | — | 3.3" | 0" | ❄️ Dormant |
| May | 6.5" | 4" | 2.5" | 💧 Light watering |
| Jun | 6.5" | 5.1" | 1.4" | 💧 Light watering |
| Jul | 6.5" | 3.9" | 2.6" | 💧 Light watering |
| Aug | 6.5" | 3.9" | 2.6" | 💧 Light watering |
| Sep | 6.5" | 2.9" | 3.6" | 🚿 Regular watering |
| Oct | 6.5" | 2.4" | 4.1" | 🚿 Regular watering |
| Nov | — | 2.8" | 0" | ❄️ Dormant |
| Dec | — | 2" | 0" | ❄️ Dormant |
Water needs are for active growing months only (May–Oct in Mitchell 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 — Mitchell County, IA
Napa Cabbage Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 29 | Mar 29 – Apr 12 |
| Transplant Outdoors | May 3 | May 3 – May 17 |
| Direct Sow | April 19 | Apr 19 – May 10 |
| Harvest | June 28 | Jun 28 – Aug 2 |
| Fall Sowing | July 29 | Jul 29 – Aug 12 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | Start Indoors Direct Sow |
| May | Transplant Outdoors Direct Sow |
| June | Harvest |
| July | Fall Sowing Harvest |
| August | Fall Sowing Harvest |
| September | — |
| 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: acceptable
🗺️ USDA Zone
Zone 5a
📆 Growing Season
157 days in Mitchell County
Growing Tips for Napa Cabbage in Mitchell County
Direct sow Napa Cabbage outdoors after May 03 in Mitchell 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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Check more plant combinations with our Companion Planting Checker →
Napa Cabbage in Other Locations
Frequently Asked Questions
When should I plant Napa Cabbage in Mitchell County, IA?
Mitchell County is in Zone 5a with an average last frost of May 3. Plan your Napa Cabbage planting based on this frost date — see the calendar above for exact timing.
What planting zone is Mitchell County, IA?
Mitchell County, Iowa is in USDA Hardiness Zone 5a. The average last spring frost is May 3 and first fall frost is October 7.
When should I plant Napa Cabbage in Mitchell County, IA?
In Mitchell County, IA, plant Napa Cabbage after the last frost (around May 3) and before the first frost (around October 7). Best results when soil holds above 50°F.
What growing zone is Mitchell County, IA for Napa Cabbage?
Mitchell County sits in USDA Zone 5a. Napa Cabbage grows reliably in zones 2a through 11b, so it's a good fit here.
Can Napa Cabbage grow in Mitchell County's climate?
Yes — Napa Cabbage grows well in Mitchell County's temperate climate. Mitchell County averages a 157-day frost-free season, with last frost around May 3 and first frost around October 7.
Your Mitchell County Garden Planner — Free
A 22-page printable planner built for Mitchell County (Zone 5a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.