When to Plant Cabbage in Iroquois County, IL
Your May planting checklist for Iroquois County, Illinois
May is a pivotal month for Iroquois County, Illinois gardens. Focus on these tasks first and you'll set up the rest of the season for success.
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Sow cabbage in trays indoors
These need a head start before your last frost (April 18). Sow into cells now so you're ready to transplant in a few weeks.
June will be here before you know it — start on
- 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.
Iroquois County, Illinois is in USDA Zone 5b. The average last spring frost is April 18 and the first fall frost is October 13, giving you a growing season of approximately 178 days.
At an elevation of 1,345 feet, Iroquois County receives approximately 30 inches of rainfall annually with predominantly silt loam soil. Summer highs average 85°F, providing good warmth for Cabbage during the growing season.
Iroquois County Soil Profile
Soil Type
Silt Loam
Soil pH
5.9-6.7
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 Iroquois County
How your county's soil matches Cabbage's growing requirements.
Soil pH
Your soil pH (5.9–6.7) overlaps with Cabbage's range (6.0–7.5), though not a perfect match.
Soil Texture
The silt loam soil in Iroquois County is excellent for Cabbage — good drainage, moisture retention, and nutrient holding capacity.
Drainage
Drainage is adequate for Cabbage.
Organic Matter
Organic matter is excellent (4.5%) — 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 05 to harvest before frost.
For a dedicated fall crop, sow by Aug 04.
Plant Water Budget
Water stress score is 6/10 — consider drought-tolerant varieties and mulching
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 | — | 1.4" | 0" | ❄️ Dormant |
| Mar | — | 1.9" | 0" | ❄️ Dormant |
| Apr | 3.9" | 2.8" | 1.1" | 💧 Light watering |
| May | 3.9" | 3.8" | 0.1" | 💧 Light watering |
| Jun | 3.9" | 3.6" | 0.3" | 💧 Light watering |
| Jul | 3.9" | 3" | 0.9" | 💧 Light watering |
| Aug | 3.9" | 2.9" | 1" | 💧 Light watering |
| Sep | 3.9" | 3.2" | 0.7" | 💧 Light watering |
| Oct | 3.9" | 2.5" | 1.4" | 💧 Light watering |
| Nov | — | 2" | 0" | ❄️ Dormant |
| Dec | — | 1.6" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Iroquois 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 — Iroquois County, IL
Cabbage Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 14 | Mar 14 – Mar 28 |
| Transplant Outdoors | April 18 | Apr 18 – May 2 |
| Direct Sow | April 4 | Apr 4 – Apr 25 |
| Harvest | June 20 | Jun 20 – Aug 15 |
| Fall Sowing | August 4 | Aug 4 – Aug 18 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | Transplant Outdoors Direct Sow |
| May | Transplant Outdoors |
| June | Harvest |
| July | Harvest |
| August | Fall Sowing Harvest |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
0.9"/week · 1-2 times/week
📅 Days to Maturity
60–100 days
🧪 Soil pH
Needs 6–7.5 · Your soil: acceptable
🗺️ USDA Zone
Zone 5b
📆 Growing Season
178 days in Iroquois County
Growing Tips for Cabbage in Iroquois County
Direct sow Cabbage outdoors after April 18 in Iroquois 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 Iroquois County, IL?
Iroquois County is in Zone 5b with an average last frost of April 18. Plan your Cabbage planting based on this frost date — see the calendar above for exact timing.
What planting zone is Iroquois County, IL?
Iroquois County, Illinois is in USDA Hardiness Zone 5b. The average last spring frost is April 18 and first fall frost is October 13.
Your Iroquois County Garden Planner — Free
A 24-page printable planner built for Iroquois 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.