When to plant Radicchio in Cass County, IL
Plant Radicchio in Cass County after April 15; the prime window is April 1–April 22. A second sowing from August 7 to August 21 extends the harvest into fall.
When to Plant Radicchio in Cass County, IL
August to-do list for Cass County, Illinois
August rewards gardeners who work with the weather, not against it. Here's how to stay in step this month in Cass County, Illinois.
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Direct-sow radicchio for cool weather
Keep young seedlings shaded and moist in summer heat. A row of taller crops works as natural shade.
Radicchio is an Italian chicory with stunning red and white leaves and a pleasantly bitter flavor. It forms tight heads and is used in salads, grilled, or braised.
Cass County, Illinois is in USDA Zone 6a. The average last spring frost is April 15 and the first fall frost is October 16, giving you a growing season of approximately 184 days.
At an elevation of 703 feet, Cass County receives approximately 31.9 inches of rainfall annually with predominantly silt loam soil. Summer highs average 83°F, so choose short-season varieties of Radicchio to ensure they mature before fall.
Cass County Soil Profile
Soil Type
Silt Loam
Soil pH
6-7.2
Drainage
Well Drained
Radicchio 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 Cass County
How your county's soil matches Radicchio's growing requirements.
Soil pH
Your soil pH (6.0–7.2) overlaps with Radicchio's range (6.0–7.0), though not a perfect match.
Soil Texture
The silt loam soil in Cass County is excellent for Radicchio — good drainage, moisture retention, and nutrient holding capacity.
Drainage
Drainage is adequate for Radicchio.
Organic Matter
Organic matter is moderate (4.0%). Annual compost additions will help Radicchio.
How to Plant Radicchio
Fall planting: Sow 10 weeks before your first frost date for a fall harvest.
Succession Planting Radicchio
Sow every 6.9 weeks. Last sowing by Jul 28 to harvest before frost.
For a dedicated fall crop, sow by Aug 07.
Radicchio Water Budget
Water stress score is 6/10 — consider drought-tolerant varieties and mulching
Monthly Watering Guide for Radicchio
Radicchio needs approximately 0.7 inches of water per week (3" per month). Here's how your county's rainfall compares month by month.
| Month | Radicchio Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 1.4" | 0" | ❄️ Dormant |
| Feb | — | 1.4" | 0" | ❄️ Dormant |
| Mar | — | 2.3" | 0" | ❄️ Dormant |
| Apr | 3" | 2.8" | 0.2" | 💧 Light watering |
| May | 3" | 3.6" | 0" | ✅ Rainfall sufficient |
| Jun | 3" | 3.7" | 0" | ✅ Rainfall sufficient |
| Jul | 3" | 3.3" | 0" | ✅ Rainfall sufficient |
| Aug | 3" | 3.8" | 0" | ✅ Rainfall sufficient |
| Sep | 3" | 3.3" | 0" | ✅ Rainfall sufficient |
| Oct | 3" | 2.6" | 0.4" | 💧 Light watering |
| Nov | — | 2" | 0" | ❄️ Dormant |
| Dec | — | 1.6" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Cass County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Radicchio 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.
Radicchio Planting Timeline — Cass County, IL
Radicchio Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 11 | Mar 11 – Mar 25 |
| Transplant Outdoors | April 15 | Apr 15 – Apr 29 |
| Direct Sow | April 1 | Apr 1 – Apr 22 |
| Harvest | June 17 | Jun 17 – Jul 22 |
| Fall Sowing | August 7 | Aug 7 – Aug 21 |
Plant 0.5" deep · 6" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | Transplant Outdoors 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 · Only during dry spells
📅 Days to Maturity
60–80 days
🧪 Soil pH
Needs 6–7 · Your soil: acceptable
🗺️ USDA Zone
Zone 6a
📆 Growing Season
184 days in Cass County
Growing Tips for Radicchio in Cass County
Direct sow Radicchio outdoors after April 15 in Cass County when soil has warmed and frost danger has passed.
Common pests for Radicchio in this region include aphids and slugs. Use row covers early in the season and inspect plants weekly.
General growing tips
Start in late summer for fall harvest. The red color develops with cool nights and light frost. Harvest when heads are firm and compact.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Radicchio in Other Locations
Frequently Asked Questions
When should I plant Radicchio in Cass County, IL?
Cass County is in Zone 6a with an average last frost of April 15. Plan your Radicchio planting based on this frost date — see the calendar above for exact timing.
What planting zone is Cass County, IL?
Cass County, Illinois is in USDA Hardiness Zone 6a. The average last spring frost is April 15 and first fall frost is October 16.
When should I plant Radicchio in Cass County, IL?
In Cass County, IL, plant Radicchio after the last frost (around April 15) and before the first frost (around October 16). Best results when soil holds above 50°F.
What growing zone is Cass County, IL for Radicchio?
Cass County sits in USDA Zone 6a. Radicchio grows reliably in zones 4a through 10b, so it's a good fit here.
Can Radicchio grow in Cass County's climate?
Yes — Radicchio grows well in Cass County's temperate climate. Cass County averages a 184-day frost-free season, with last frost around April 15 and first frost around October 16.
Your Cass County Garden Planner — Free
A 22-page printable planner built for Cass County (Zone 6a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.