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When to Plant Kohlrabi in Lewis County, TN

Lewis County, Tennessee Zone 7b May

Your May game plan for Lewis County, Tennessee

If you only do a handful of things in the garden this May, make it these. They're sequenced around your zone's frost timing.

Avg. last frost April 9
Avg. first frost October 26
Soil temp (4") 57°F
Watering Low
Pest pressure Moderate
Daylight 13.9 hrs
  1. Indoor seed-starting week for kohlrabi

    Starting these indoors now means sturdy transplants ready the moment your soil warms up.

  2. It's harvest week for kohlrabi

    The more you pick, the more the plant produces. Letting fruit overripen tells the plant it's time to stop.

To set up a strong June, finish these tasks
  • First harvests: kohlrabi

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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.

Lewis County, Tennessee is in USDA Zone 7b. The average last spring frost is April 9 and the first fall frost is October 26, giving you a growing season of approximately 200 days.

At an elevation of 3,735 feet, Lewis County receives approximately 52.2 inches of rainfall annually with predominantly silt loam soil. Summer highs average 88°F, providing good warmth for Kohlrabi during the growing season. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Kohlrabi root diseases.

Lewis County, TN (Zone 7b) Long season
200 days
Last Spring Frost April 9
200 growing days
First Fall Frost October 26

Lewis County Soil Profile

Soil Type

Silt Loam

Soil pH

5.5-6.9

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (116 days to spare)
Start indoors: Feb 27 Transplant: Apr 3 🍅 Harvest: May 22 – Jun 26
Recommended (50%) ✓ Fits season (116 days to spare)
Start indoors: Mar 5 Transplant: Apr 9 🍅 Harvest: May 28 – Jul 2
Safe Start (90%) ✓ Fits season (117 days to spare)
Start indoors: Mar 20 Transplant: Apr 24 🍅 Harvest: Jun 12 – Jul 17

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 Lewis County

How your county's soil matches Kohlrabi's growing requirements.

Soil pH

Your soil pH (5.5–6.9) overlaps with Kohlrabi's range (6.0–7.5), though not a perfect match.

Soil Texture

The silt loam soil in Lewis County is excellent for Kohlrabi — good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is moderate (3.0%). Annual compost additions will help Kohlrabi.

How to Plant Kohlrabi

0.5"
Planting Depth
4"
Between Plants
12"
Between Rows

Fall planting: Sow 10 weeks before your first frost date for a fall harvest.

Succession Planting Kohlrabi

5
successive plantings in your 200-day season

Sow every 5.1 weeks. Last sowing by Aug 22 to harvest before frost.

For a dedicated fall crop, sow by Aug 17.

Plant Water Budget

Plant needs
0.7″/week
Rainfall provides
1.1″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft
Drought risk

Water stress score is 6/10 — consider drought-tolerant varieties and mulching

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 4.6" 0" ❄️ Dormant
Feb 4.5" 0" ❄️ Dormant
Mar 5.2" 0" ❄️ Dormant
Apr 3" 3.6" 0" ✅ Rainfall sufficient
May 3" 3.8" 0" ✅ Rainfall sufficient
Jun 3" 4.2" 0" ✅ Rainfall sufficient
Jul 3" 5.4" 0" ✅ Rainfall sufficient
Aug 3" 5.2" 0" ✅ Rainfall sufficient
Sep 3" 4.2" 0" ✅ Rainfall sufficient
Oct 3" 3.8" 0" ✅ Rainfall sufficient
Nov 3.7" 0" ❄️ Dormant
Dec 3.8" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Lewis 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 needs ~880 GDD — county provides 3,200 GDD Excellent fit

Kohlrabi Planting Timeline — Lewis County, TN

Kohlrabi Planting Calendar

Activity When Date Range
Start Indoors March 5 Mar 5 – Mar 19
Transplant Outdoors April 9 Apr 9 – Apr 23
Direct Sow March 26 Mar 26 – Apr 16
Harvest May 28 May 28 – Jul 2
Fall Sowing August 17 Aug 17 – Aug 31

Plant 0.5" deep · 4" apart · Rows 12" apart

Month-by-Month Timeline

MonthActivities
January
February
March Start Indoors Direct Sow
April Transplant Outdoors Direct Sow
May Harvest
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

45–65 days

🧪 Soil pH

Needs 6–7.5 · Your soil: acceptable

🗺️ USDA Zone

Zone 7b

📆 Growing Season

200 days in Lewis County

Growing Tips for Kohlrabi in Lewis County

Direct sow Kohlrabi outdoors after April 09 in Lewis County when soil has warmed and frost danger has passed.

Your generous 200.0-day season in Lewis 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

  • Tomatoes
  • Strawberries

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Kohlrabi in Lewis County, TN?

Lewis County is in Zone 7b with an average last frost of April 9. Plan your Kohlrabi planting based on this frost date — see the calendar above for exact timing.

What planting zone is Lewis County, TN?

Lewis County, Tennessee is in USDA Hardiness Zone 7b. The average last spring frost is April 9 and first fall frost is October 26.

🌱

Your Lewis County Garden Planner — Free

A 24-page printable planner built for Lewis 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.

Instant PDF download. No spam, unsubscribe any time.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Lewis County, TN. Local conditions may vary. Last updated: May 2026.

Sources & credits

Every number on this page traces back to a primary horticulture or government data source. Click through to verify.