When to Plant Kohlrabi in Benton County, TN
May to-do list for Benton County, Tennessee
Welcome to May in Zone 7b. These are the moves that will have the biggest impact on your growing season.
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Get kohlrabi seeds going inside
Give them 6–8 weeks indoors before the last frost and you'll transplant into warm soil with seedlings that are already leaping.
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Start harvesting kohlrabi
Morning harvests are best — cooler temperatures mean crisper produce and longer fridge life.
June will be here before you know it — start on
- First harvests: kohlrabi
Kohlrabi is an unusual brassica that forms a swollen stem above ground with a mild, sweet turnip-like flavor. Both the bulb and tender leaves are edible.
Benton County, Tennessee is in USDA Zone 7b. The average last spring frost is April 7 and the first fall frost is October 28, giving you a growing season of approximately 204 days.
At an elevation of 3,295 feet, Benton County receives approximately 46.9 inches of rainfall annually with predominantly silt loam soil. Summer highs average 91°F, providing good warmth for Kohlrabi during the growing season.
Benton County Soil Profile
Soil Type
Silt Loam
Soil pH
5.5-7.1
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 Benton County
How your county's soil matches Kohlrabi's growing requirements.
Soil pH
Your soil pH (5.5–7.1) overlaps with Kohlrabi's range (6.0–7.5), though not a perfect match.
Soil Texture
The silt loam soil in Benton County is excellent for Kohlrabi — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (2.9%). Annual compost additions will help Kohlrabi.
How to Plant Kohlrabi
Fall planting: Sow 10 weeks before your first frost date for a fall harvest.
Succession Planting Kohlrabi
Sow every 5.1 weeks. Last sowing by Aug 24 to harvest before frost.
For a dedicated fall crop, sow by Aug 19.
Plant Water Budget
Monthly Watering Guide for Kohlrabi
Kohlrabi needs approximately 0.7 inches of water per week (3" per month). Here's how your county's rainfall compares month by month.
| Month | Kohlrabi Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 3.8" | 0" | ❄️ Dormant |
| Feb | — | 4.1" | 0" | ❄️ Dormant |
| Mar | — | 4.3" | 0" | ❄️ Dormant |
| Apr | 3" | 3.2" | 0" | ✅ Rainfall sufficient |
| May | 3" | 3.2" | 0" | ✅ Rainfall sufficient |
| Jun | 3" | 3.9" | 0" | ✅ Rainfall sufficient |
| Jul | 3" | 5.2" | 0" | ✅ Rainfall sufficient |
| Aug | 3" | 5.1" | 0" | ✅ Rainfall sufficient |
| Sep | 3" | 3.8" | 0" | ✅ Rainfall sufficient |
| Oct | 3" | 2.8" | 0.2" | 💧 Light watering |
| Nov | — | 3.4" | 0" | ❄️ Dormant |
| Dec | — | 4.1" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Benton County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Kohlrabi 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.
Kohlrabi Planting Timeline — Benton County, TN
Kohlrabi Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 3 | Mar 3 – Mar 17 |
| Transplant Outdoors | April 7 | Apr 7 – Apr 21 |
| Direct Sow | March 24 | Mar 24 – Apr 14 |
| Harvest | May 26 | May 26 – Jun 30 |
| Fall Sowing | August 19 | Aug 19 – Sep 2 |
Plant 0.5" deep · 4" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors Direct Sow |
| April | Transplant Outdoors Direct Sow |
| May | Harvest |
| June | Harvest |
| July | — |
| August | Fall Sowing |
| September | Fall Sowing |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
0.7"/week · Natural rainfall sufficient
📅 Days to Maturity
45–65 days
🧪 Soil pH
Needs 6–7.5 · Your soil: acceptable
🗺️ USDA Zone
Zone 7b
📆 Growing Season
204 days in Benton County
Growing Tips for Kohlrabi in Benton County
Direct sow Kohlrabi outdoors after April 07 in Benton County when soil has warmed and frost danger has passed.
Your generous 204.0-day season in Benton County allows multiple plantings of Kohlrabi. Sow every 22.0 days for continuous harvest.
Common pests for Kohlrabi 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 spring or fall. Harvest when bulbs are 2-3 inches in diameter for best texture and flavor. Larger bulbs may become woody and fibrous.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Kohlrabi in Other Locations
Frequently Asked Questions
When should I plant Kohlrabi in Benton County, TN?
Benton County is in Zone 7b with an average last frost of April 7. Plan your Kohlrabi planting based on this frost date — see the calendar above for exact timing.
What planting zone is Benton County, TN?
Benton County, Tennessee is in USDA Hardiness Zone 7b. The average last spring frost is April 7 and first fall frost is October 28.
Your Benton County Garden Planner — Free
A 24-page printable planner built for Benton County (Zone 7b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.