When to plant Radicchio in Johnson County, KY
Johnson County gardeners should plant Radicchio between March 31 and April 21 in spring. With Johnson County's Zone 7a climate (last frost April 14), Radicchio needs 60–80 days to mature — plant by August 7 for a full harvest. A second sowing from August 17 to August 31 extends the harvest into fall.
When to Plant Radicchio in Johnson County, KY
What to do in June
Welcome to June in Zone 7a. These are the moves that will have the biggest impact on your growing season.
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Harvest radicchio as they ripen
Morning harvests are best — cooler temperatures mean crisper produce and longer fridge life.
Looking ahead to July
- First harvests: radicchio
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.
Johnson County, Kentucky is in USDA Zone 7a. The average last spring frost is April 14 and the first fall frost is October 26, giving you a growing season of approximately 195 days.
At an elevation of 3,308 feet, Johnson County receives approximately 47 inches of rainfall annually with predominantly silt loam soil. Summer highs average 86°F, providing good warmth for Radicchio during the growing season.
Johnson County Soil Profile
Soil Type
Silt Loam
Soil pH
5.3-7
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 Johnson County
How your county's soil matches Radicchio's growing requirements.
Soil pH
Your soil pH (5.3–7.0) overlaps with Radicchio's range (6.0–7.0), though not a perfect match.
Soil Texture
The silt loam soil in Johnson 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 (3.0%). 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 Aug 07 to harvest before frost.
For a dedicated fall crop, sow by Aug 17.
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 | — | 3.4" | 0" | ❄️ Dormant |
| Feb | — | 4.2" | 0" | ❄️ Dormant |
| Mar | — | 5.1" | 0" | ❄️ Dormant |
| Apr | 3" | 4.1" | 0" | ✅ Rainfall sufficient |
| May | 3" | 3.5" | 0" | ✅ Rainfall sufficient |
| Jun | 3" | 4.6" | 0" | ✅ Rainfall sufficient |
| Jul | 3" | 4.6" | 0" | ✅ Rainfall sufficient |
| Aug | 3" | 4.4" | 0" | ✅ Rainfall sufficient |
| Sep | 3" | 3.5" | 0" | ✅ Rainfall sufficient |
| Oct | 3" | 2.6" | 0.4" | 💧 Light watering |
| Nov | — | 3.6" | 0" | ❄️ Dormant |
| Dec | — | 3.5" | 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.
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 — Johnson County, KY
Radicchio Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 10 | Mar 10 – Mar 24 |
| Transplant Outdoors | April 14 | Apr 14 – Apr 28 |
| Direct Sow | March 31 | Mar 31 – Apr 21 |
| Harvest | June 16 | Jun 16 – Jul 21 |
| Fall Sowing | August 17 | Aug 17 – Aug 31 |
Plant 0.5" deep · 6" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors Direct Sow |
| 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 · Natural rainfall sufficient
📅 Days to Maturity
60–80 days
🧪 Soil pH
Needs 6–7 · Your soil: acceptable
🗺️ USDA Zone
Zone 7a
📆 Growing Season
195 days in Johnson County
Growing Tips for Radicchio in Johnson County
Direct sow Radicchio outdoors after April 14 in Johnson 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 Johnson County, KY?
Johnson County is in Zone 7a with an average last frost of April 14. Plan your Radicchio planting based on this frost date — see the calendar above for exact timing.
What planting zone is Johnson County, KY?
Johnson County, Kentucky is in USDA Hardiness Zone 7a. The average last spring frost is April 14 and first fall frost is October 26.
When should I plant Radicchio in Johnson County, KY?
In Johnson County, KY, plant Radicchio after the last frost (around April 14) and before the first frost (around October 26). Best results when soil holds above 50°F.
What growing zone is Johnson County, KY for Radicchio?
Johnson County sits in USDA Zone 7a. Radicchio grows reliably in zones 4a through 10b, so it's a good fit here.
Can Radicchio grow in Johnson County's climate?
Yes — Radicchio grows well in Johnson County's temperate climate. Johnson County averages a 195-day frost-free season, with last frost around April 14 and first frost around October 26.
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.