When to Plant Radicchio in St. Joseph County, IN
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.
St. Joseph County, Indiana is in USDA Zone 5b. The average last spring frost is April 29 and the first fall frost is October 17, giving you a growing season of approximately 171 days.
At an elevation of 1,398 feet, St. Joseph County receives approximately 40.7 inches of rainfall annually with predominantly silt loam soil. Summer highs average 84°F, so choose short-season varieties of Radicchio to ensure they mature before fall.
St. Joseph County Soil Profile
Soil Type
Silt Loam
Soil pH
6-6.8
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 St. Joseph County
How your county's soil matches Radicchio's growing requirements.
Soil pH
Your soil pH (6.0–6.8) is within Radicchio's preferred range (6.0–7.0).
Soil Texture
The silt loam soil in St. Joseph County is excellent for Radicchio — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is excellent (4.3%) — Radicchio will thrive.
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 29 to harvest before frost.
For a dedicated fall crop, sow by Aug 08.
Plant Water Budget
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 | — | 1.7" | 0" | ❄️ Dormant |
| Feb | — | 2.1" | 0" | ❄️ Dormant |
| Mar | — | 2.5" | 0" | ❄️ Dormant |
| Apr | 3" | 3.9" | 0" | ✅ Rainfall sufficient |
| May | 3" | 4.6" | 0" | ✅ Rainfall sufficient |
| Jun | 3" | 5.1" | 0" | ✅ Rainfall sufficient |
| Jul | 3" | 4.7" | 0" | ✅ Rainfall sufficient |
| Aug | 3" | 3.9" | 0" | ✅ Rainfall sufficient |
| Sep | 3" | 4" | 0" | ✅ Rainfall sufficient |
| Oct | 3" | 3.3" | 0" | ✅ Rainfall sufficient |
| Nov | — | 2.9" | 0" | ❄️ Dormant |
| Dec | — | 2.1" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in St. Joseph 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 — St. Joseph County, IN
Radicchio Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 25 | Mar 25 – Apr 8 |
| Transplant Outdoors | April 29 | Apr 29 – May 13 |
| Direct Sow | April 15 | Apr 15 – May 6 |
| Harvest | July 1 | Jul 1 – Aug 5 |
| Fall Sowing | August 8 | Aug 8 – Aug 22 |
Plant 0.5" deep · 6" apart · Rows 12" 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 | Harvest |
| August | Fall Sowing Harvest |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
0.7"/week · Natural rainfall sufficient
📅 Days to Maturity
60–80 days
🧪 Soil pH
Needs 6–7 · Your soil: ideal
🗺️ USDA Zone
Zone 5b
📆 Growing Season
171 days in St. Joseph County
Growing Tips for Radicchio in St. Joseph County
Direct sow Radicchio outdoors after April 29 in St. Joseph 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
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Radicchio in Other Locations
Frequently Asked Questions
When should I plant Radicchio in St. Joseph County, IN?
St. Joseph County is in Zone 5b with an average last frost of April 29. Plan your Radicchio planting based on this frost date — see the calendar above for exact timing.
What planting zone is St. Joseph County, IN?
St. Joseph County, Indiana is in USDA Hardiness Zone 5b. The average last spring frost is April 29 and first fall frost is October 17.
Plan Your Garden with Confidence
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