When to plant Rutabaga in Johnson County, IL
The best window to plant Rutabaga in Johnson County, is March 24–April 14, when soil warms to 50°F. Last frost typically hits April 7; first frost October 21. A second sowing from August 12 to August 26 extends the harvest into fall.
When to Plant Rutabaga in Johnson County, IL
Johnson County, Illinois gardeners: here's your June plan
Welcome to June in Zone 7a. These are the moves that will have the biggest impact on your growing season.
-
Basket week: rutabaga
Taste as you pick. The first ripe produce is the best feedback loop you'll get all season.
Get ahead of July
- First harvests: rutabaga
Rutabagas are a cross between turnips and cabbage, producing large yellow-fleshed roots with a sweet, mild flavor. They are excellent mashed, roasted, or in stews.
Johnson County, Illinois is in USDA Zone 7a. The average last spring frost is April 7 and the first fall frost is October 21, giving you a growing season of approximately 197 days.
At an elevation of 1,006 feet, Johnson County receives approximately 39.7 inches of rainfall annually with predominantly silt loam soil. Summer highs average 90°F, providing good warmth for Rutabaga during the growing season.
Johnson County Soil Profile
Soil Type
Silt Loam
Soil pH
5.9-7.2
Drainage
Well Drained
Rutabaga 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 Johnson County
How your county's soil matches Rutabaga's growing requirements.
Soil pH
Your soil pH (5.9–7.2) overlaps with Rutabaga's range (6.0–7.5), though not a perfect match.
Soil Texture
The silt loam soil in Johnson County is excellent for Rutabaga — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is excellent (4.8%) — Rutabaga will thrive.
How to Plant Rutabaga
Fall planting: Sow 10 weeks before your first frost date for a fall harvest.
Succession Planting Rutabaga
Sow every 9.1 weeks. Last sowing by Jul 13 to harvest before frost.
For a dedicated fall crop, sow by Aug 12.
Rutabaga Water Budget
Water stress score is 6/10 — consider drought-tolerant varieties and mulching
Monthly Watering Guide for Rutabaga
Rutabaga needs approximately 0.7 inches of water per week (3" per month). Here's how your county's rainfall compares month by month.
| Month | Rutabaga Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 1.6" | 0" | ❄️ Dormant |
| Feb | — | 1.9" | 0" | ❄️ Dormant |
| Mar | — | 2.9" | 0" | ❄️ Dormant |
| Apr | 3" | 3.6" | 0" | ✅ Rainfall sufficient |
| May | 3" | 4.2" | 0" | ✅ Rainfall sufficient |
| Jun | 3" | 4.4" | 0" | ✅ Rainfall sufficient |
| Jul | 3" | 4.8" | 0" | ✅ Rainfall sufficient |
| Aug | 3" | 4.6" | 0" | ✅ Rainfall sufficient |
| Sep | 3" | 3.3" | 0" | ✅ Rainfall sufficient |
| Oct | 3" | 3.2" | 0" | ✅ Rainfall sufficient |
| Nov | — | 2.9" | 0" | ❄️ Dormant |
| Dec | — | 2.3" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Johnson County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Rutabaga 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.
Rutabaga Planting Timeline — Johnson County, IL
Rutabaga Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Direct Sow | March 24 | Mar 24 – Apr 14 |
| Harvest | June 16 | Jun 16 – Jul 21 |
| Fall Sowing | August 12 | Aug 12 – Aug 26 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Direct Sow |
| April | Direct Sow |
| May | — |
| June | Harvest |
| July | Harvest |
| August | Fall Sowing |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
0.7"/week · Natural rainfall sufficient
📅 Days to Maturity
80–100 days
🧪 Soil pH
Needs 6–7.5 · Your soil: acceptable
🗺️ USDA Zone
Zone 7a
📆 Growing Season
197 days in Johnson County
Growing Tips for Rutabaga in Johnson County
Direct sow Rutabaga outdoors after April 07 in Johnson County when soil has warmed and frost danger has passed.
Common pests for Rutabaga in this region include cabbage worm and flea beetles. Use row covers early in the season and inspect plants weekly.
General growing tips
Direct sow in early summer for fall harvest. Thin seedlings to 6-8 inches apart. Flavor improves significantly after a few light frosts.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Rutabaga in Other Locations
Frequently Asked Questions
When should I plant Rutabaga in Johnson County, IL?
Johnson County is in Zone 7a with an average last frost of April 7. Plan your Rutabaga planting based on this frost date — see the calendar above for exact timing.
What planting zone is Johnson County, IL?
Johnson County, Illinois is in USDA Hardiness Zone 7a. The average last spring frost is April 7 and first fall frost is October 21.
When should I plant Rutabaga in Johnson County, IL?
In Johnson County, IL, plant Rutabaga after the last frost (around April 7) and before the first frost (around October 21). Best results when soil holds above 50°F.
What growing zone is Johnson County, IL for Rutabaga?
Johnson County sits in USDA Zone 7a. Rutabaga grows reliably in zones 2a through 9b, so it's a good fit here.
Can Rutabaga grow in Johnson County's climate?
Yes — Rutabaga grows well in Johnson County's temperate climate. Johnson County averages a 197-day frost-free season, with last frost around April 7 and first frost around October 21.
Your Johnson County Garden Planner — Free
A 22-page printable planner built for Johnson County (Zone 7a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.