When to Plant Cabbage in Mahaska County, IA
Your May gardening checklist
Your garden in Mahaska County, Iowa is working on a schedule, even when you're not. Here's where you should be this May.
Before June arrives, get these ready
- Starting indoors: cabbage
- First harvests: cabbage
Cabbage is a versatile cool-season crop that forms dense, leafy heads in green, red, or savoy varieties. It is a staple for coleslaw, sauerkraut, and many global cuisines.
Mahaska County, Iowa is in USDA Zone 5b. The average last spring frost is April 27 and the first fall frost is October 9, giving you a growing season of approximately 165 days.
At an elevation of 511 feet, Mahaska County receives approximately 32.2 inches of rainfall annually with predominantly silt loam soil. Summer highs average 83°F, so choose short-season varieties of Cabbage to ensure they mature before fall.
Mahaska County Soil Profile
Soil Type
Silt Loam
Soil pH
5.7-7.3
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 Mahaska County
How your county's soil matches Cabbage's growing requirements.
Soil pH
Your soil pH (5.7–7.3) overlaps with Cabbage's range (6.0–7.5), though not a perfect match.
Soil Texture
The silt loam soil in Mahaska County is excellent for Cabbage — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is excellent (4.1%) — Cabbage will thrive.
How to Plant Cabbage
Fall planting: Sow 10 weeks before your first frost date for a fall harvest.
Succession Planting Cabbage
Sow every 6.9 weeks. Last sowing by Jul 01 to harvest before frost.
For a dedicated fall crop, sow by Jul 31.
Plant Water Budget
Monthly Watering Guide for Cabbage
Cabbage needs approximately 0.9 inches of water per week (3.9" per month). Here's how your county's rainfall compares month by month.
| Month | Cabbage Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 1.1" | 0" | ❄️ Dormant |
| Feb | — | 1.3" | 0" | ❄️ Dormant |
| Mar | — | 2.5" | 0" | ❄️ Dormant |
| Apr | 3.9" | 3.1" | 0.8" | 💧 Light watering |
| May | 3.9" | 3.4" | 0.5" | 💧 Light watering |
| Jun | 3.9" | 4.5" | 0" | ✅ Rainfall sufficient |
| Jul | 3.9" | 3.3" | 0.6" | 💧 Light watering |
| Aug | 3.9" | 3.2" | 0.7" | 💧 Light watering |
| Sep | 3.9" | 3.2" | 0.7" | 💧 Light watering |
| Oct | 3.9" | 2.4" | 1.5" | 💧 Light watering |
| Nov | — | 2.4" | 0" | ❄️ Dormant |
| Dec | — | 1.9" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Mahaska County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
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.
Cabbage Planting Timeline — Mahaska County, IA
Cabbage Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 23 | Mar 23 – Apr 6 |
| Transplant Outdoors | April 27 | Apr 27 – May 11 |
| Direct Sow | April 13 | Apr 13 – May 4 |
| Harvest | June 29 | Jun 29 – Aug 24 |
| Fall Sowing | July 31 | Jul 31 – Aug 14 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | Start Indoors Transplant Outdoors Direct Sow |
| May | Transplant Outdoors Direct Sow |
| June | Harvest |
| July | Fall Sowing Harvest |
| August | Fall Sowing Harvest |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
0.9"/week · Only during dry spells
📅 Days to Maturity
60–100 days
🧪 Soil pH
Needs 6–7.5 · Your soil: acceptable
🗺️ USDA Zone
Zone 5b
📆 Growing Season
165 days in Mahaska County
Growing Tips for Cabbage in Mahaska County
Direct sow Cabbage outdoors after April 27 in Mahaska County when soil has warmed and frost danger has passed.
Common pests for Cabbage in this region include cabbage worm and flea beetles. Use row covers early in the season and inspect plants weekly.
General growing tips
Start seeds indoors 4-6 weeks before last frost. Space plants 18-24 inches apart. Keep soil evenly moist to prevent heads from splitting.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Cabbage in Other Locations
Frequently Asked Questions
When should I plant Cabbage in Mahaska County, IA?
Mahaska County is in Zone 5b with an average last frost of April 27. Plan your Cabbage planting based on this frost date — see the calendar above for exact timing.
What planting zone is Mahaska County, IA?
Mahaska County, Iowa is in USDA Hardiness Zone 5b. The average last spring frost is April 27 and first fall frost is October 9.
Your Mahaska County Garden Planner — Free
A 24-page printable planner built for Mahaska County (Zone 5b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.