When to Plant Radish in Clay County, TN
Radishes are one of the fastest-growing vegetables, with some varieties ready in under a month. They come in round, elongated, and large winter types.
Clay County, Tennessee is in USDA Zone 6b. The average last spring frost is April 12 and the first fall frost is October 27, giving you a growing season of approximately 198 days.
At an elevation of 1,418 feet, Clay County receives approximately 42.5 inches of rainfall annually with predominantly silt loam soil. Summer highs average 86°F, providing good warmth for Radish during the growing season.
Clay County Soil Profile
Soil Type
Silt Loam
Soil pH
5.7-7.1
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 Clay County
How your county's soil matches Radish's growing requirements.
Soil pH
Your soil pH (5.7–7.1) overlaps with Radish's range (6.0–7.0), though not a perfect match.
Soil Texture
The silt loam soil in Clay County is excellent for Radish — good drainage, moisture retention, and nutrient holding capacity.
Drainage
Drainage is adequate for Radish.
Organic Matter
Organic matter is moderate (2.6%). Annual compost additions will help Radish.
How to Plant Radish
Fall planting: Sow 10 weeks before your first frost date for a fall harvest.
Succession Planting Radish
Sow every 2.4 weeks. Last sowing by Sep 22 to harvest before frost.
For a dedicated fall crop, sow by Aug 18.
Plant Water Budget
Water stress score is 6/10 — consider drought-tolerant varieties and mulching
Monthly Watering Guide for Radish
Radish needs approximately 0.5 inches of water per week (2.2" per month). Here's how your county's rainfall compares month by month.
| Month | Radish Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 3.9" | 0" | ❄️ Dormant |
| Feb | — | 3.5" | 0" | ❄️ Dormant |
| Mar | — | 4" | 0" | ❄️ Dormant |
| Apr | 2.2" | 3.6" | 0" | ✅ Rainfall sufficient |
| May | 2.2" | 3" | 0" | ✅ Rainfall sufficient |
| Jun | 2.2" | 3.6" | 0" | ✅ Rainfall sufficient |
| Jul | 2.2" | 4.4" | 0" | ✅ Rainfall sufficient |
| Aug | 2.2" | 4.3" | 0" | ✅ Rainfall sufficient |
| Sep | 2.2" | 3" | 0" | ✅ Rainfall sufficient |
| Oct | 2.2" | 2.4" | 0" | ✅ Rainfall sufficient |
| Nov | — | 3.3" | 0" | ❄️ Dormant |
| Dec | — | 3.5" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Clay County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Radish 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.
Radish Planting Timeline — Clay County, TN
Radish Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Direct Sow | March 29 | Mar 29 – Apr 19 |
| Harvest | April 26 | Apr 26 – May 17 |
| Fall Sowing | August 18 | Aug 18 – Sep 1 |
Plant 0.5" deep · 2" apart · Rows 6" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Direct Sow |
| April | Direct Sow Harvest |
| May | Harvest |
| June | — |
| July | — |
| August | Fall Sowing |
| September | Fall Sowing |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
0.5"/week · Natural rainfall sufficient
📅 Days to Maturity
22–35 days
🧪 Soil pH
Needs 6–7 · Your soil: acceptable
🗺️ USDA Zone
Zone 6b
📆 Growing Season
198 days in Clay County
Growing Tips for Radish in Clay County
Direct sow Radish outdoors after April 12 in Clay County when soil has warmed and frost danger has passed.
Your generous 198.0-day season in Clay County allows multiple plantings of Radish. Sow every 11.0 days for continuous harvest.
Common pests for Radish 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 every 1-2 weeks for continuous harvest. Do not transplant. Harvest spring radishes promptly to prevent them from becoming pithy and hot.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Radish in Other Locations
Frequently Asked Questions
When should I plant Radish in Clay County, TN?
Clay County is in Zone 6b with an average last frost of April 12. Plan your Radish planting based on this frost date — see the calendar above for exact timing.
What planting zone is Clay County, TN?
Clay County, Tennessee is in USDA Hardiness Zone 6b. The average last spring frost is April 12 and first fall frost is October 27.
Plan Your Garden with Confidence
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