When to plant Cabbage in Shelby County, IA
For Cabbage in Shelby County, the safe spring window opens around April 16 and closes around May 7. Last expected frost is April 30, first fall frost October 3, giving a 156-day growing season. A second sowing from July 25 to August 8 extends the harvest into fall.
When to Plant Cabbage in Shelby County, IA
Top priorities for Shelby County, Iowa gardeners in July
If you only do a handful of things in the garden this July, make it these. They're sequenced around your zone's frost timing.
-
Pick cabbage
The more you pick, the more the plant produces. Letting fruit overripen tells the plant it's time to stop.
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Kick off the fall garden with cabbage
Your first frost is about 12 weeks away — plenty of time for these to mature.
Before August arrives, get these ready
- 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.
Shelby County, Iowa is in USDA Zone 5a. The average last spring frost is April 30 and the first fall frost is October 3, giving you a growing season of approximately 156 days.
At an elevation of 1,113 feet, Shelby County receives approximately 30.1 inches of rainfall annually with predominantly silt loam soil. Summer highs average 86°F, providing good warmth for Cabbage during the growing season.
Shelby County Soil Profile
Soil Type
Silt Loam
Soil pH
6.2-7
Drainage
Well Drained
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 Shelby County
How your county's soil matches Cabbage's growing requirements.
Soil pH
Your soil pH (6.2–7.0) is within Cabbage's preferred range (6.0–7.5).
Soil Texture
The silt loam soil in Shelby 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 Jun 25 to harvest before frost.
For a dedicated fall crop, sow by Jul 25.
Cabbage 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 | — | 1.3" | 0" | ❄️ Dormant |
| Feb | — | 1.1" | 0" | ❄️ Dormant |
| Mar | — | 2.1" | 0" | ❄️ Dormant |
| Apr | 3.9" | 2.8" | 1.1" | 💧 Light watering |
| May | 3.9" | 3.7" | 0.2" | 💧 Light watering |
| Jun | 3.9" | 3.8" | 0.1" | 💧 Light watering |
| Jul | 3.9" | 3.5" | 0.4" | 💧 Light watering |
| Aug | 3.9" | 2.9" | 1" | 💧 Light watering |
| Sep | 3.9" | 2.8" | 1.1" | 💧 Light watering |
| Oct | 3.9" | 2.5" | 1.4" | 💧 Light watering |
| Nov | — | 2" | 0" | ❄️ Dormant |
| Dec | — | 1.7" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Shelby 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 — Shelby County, IA
Cabbage Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 26 | Mar 26 – Apr 9 |
| Transplant Outdoors | April 30 | Apr 30 – May 14 |
| Direct Sow | April 16 | Apr 16 – May 7 |
| Harvest | July 2 | Jul 2 – Aug 27 |
| Fall Sowing | July 25 | Jul 25 – Aug 8 |
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 | — |
| 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: ideal
🗺️ USDA Zone
Zone 5a
📆 Growing Season
156 days in Shelby County
Growing Tips for Cabbage in Shelby County
Direct sow Cabbage outdoors after April 30 in Shelby 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 Shelby County, IA?
Shelby County is in Zone 5a with an average last frost of April 30. Plan your Cabbage planting based on this frost date — see the calendar above for exact timing.
What planting zone is Shelby County, IA?
Shelby County, Iowa is in USDA Hardiness Zone 5a. The average last spring frost is April 30 and first fall frost is October 3.
When should I plant Cabbage in Shelby County, IA?
In Shelby County, IA, plant Cabbage after the last frost (around April 30) and before the first frost (around October 3). Best results when soil holds above 50°F.
What growing zone is Shelby County, IA for Cabbage?
Shelby County sits in USDA Zone 5a. Cabbage grows reliably in zones 1a through 10b, so it's a good fit here.
Can Cabbage grow in Shelby County's climate?
Yes — Cabbage grows well in Shelby County's temperate climate. Shelby County averages a 156-day frost-free season, with last frost around April 30 and first frost around October 3.
Your Shelby County Garden Planner — Free
A 22-page printable planner built for Shelby 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.