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When to Plant Kohlrabi in Somervell County, TX

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.

Somervell County, Texas is in USDA Zone 7b. The average last spring frost is March 19 and the first fall frost is November 12, giving you a growing season of approximately 238 days.

At an elevation of 4,773 feet, Somervell County receives approximately 64.7 inches of rainfall annually with predominantly clay soil. Summer highs average 90ยฐF, providing good warmth for Kohlrabi during the growing season. Clay soil retains moisture well for Kohlrabi, but amend with compost to improve drainage and prevent root rot. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Kohlrabi root diseases.

Somervell County, TX (Zone 7b) Long season
238 days
Last Spring Frost March 19
238 growing days
First Fall Frost November 12

Somervell County Soil Profile

Soil Type

Clay

Soil pH

7.2-7.8

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (162 days to spare)
Start indoors: Feb 1 Transplant: Mar 8 🍅 Harvest: Apr 26 – May 31
Recommended (50%) ✓ Fits season (154 days to spare)
Start indoors: Feb 12 Transplant: Mar 19 🍅 Harvest: May 7 – Jun 11
Safe Start (90%) ✓ Fits season (147 days to spare)
Start indoors: Mar 8 Transplant: Apr 12 🍅 Harvest: May 31 – Jul 5

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 Somervell County

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

Soil pH

Your soil pH (7.2โ€“7.8) overlaps with Kohlrabi's range (6.0โ€“7.5), though not a perfect match.

Soil Texture

Heavy clay soil (46% clay) in Somervell County compacts easily and drains slowly. Amend with compost and avoid working soil when wet.

Organic Matter

Organic matter is moderate (3.3%). 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

6
successive plantings in your 238-day season

Sow every 5.1 weeks. Last sowing by Sep 08 to harvest before frost.

For a dedicated fall crop, sow by Sep 03.

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 โ€” 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 โ€” 1.8" 0" โ„๏ธ Dormant
Feb โ€” 2.4" 0" โ„๏ธ Dormant
Mar 3" 4.3" 0" โœ… Rainfall sufficient
Apr 3" 6.9" 0" โœ… Rainfall sufficient
May 3" 10.2" 0" โœ… Rainfall sufficient
Jun 3" 10.5" 0" โœ… Rainfall sufficient
Jul 3" 7.5" 0" โœ… Rainfall sufficient
Aug 3" 7.8" 0" โœ… Rainfall sufficient
Sep 3" 5.4" 0" โœ… Rainfall sufficient
Oct 3" 3.8" 0" โœ… Rainfall sufficient
Nov 3" 2.4" 0.6" ๐Ÿ’ง Light watering
Dec โ€” 1.7" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Marโ€“Nov in Somervell County). Supplement amounts are based on average rainfall โ€” 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" โ€” every day above 50ยฐF 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 ~962 GDD — county provides 4,165 GDD Excellent fit

Kohlrabi Planting Timeline โ€” Somervell County, TX

Kohlrabi Planting Calendar

Activity When Date Range
Start Indoors February 12 Feb 12 โ€“ Feb 26
Transplant Outdoors March 19 Mar 19 โ€“ Apr 2
Direct Sow March 5 Mar 5 โ€“ Mar 26
Harvest May 7 May 7 โ€“ Jun 11
Fall Sowing September 3 Sep 3 โ€“ Sep 17

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

Month-by-Month Timeline

MonthActivities
January โ€”
February Start Indoors
March Transplant Outdoors Direct Sow
April Transplant Outdoors
May Harvest
June Harvest
July โ€”
August โ€”
September Fall Sowing
October โ€”
November โ€”
December โ€”

Growing Conditions

โ˜€๏ธ Sun

Full Sun (6-8+ hours)

๐Ÿ’ง Water

0.7"/week ยท Natural rainfall sufficient

๐Ÿ“… Days to Maturity

45โ€“65 days

๐Ÿงช Soil pH

Needs 6โ€“7.5 ยท Your soil: acceptable

๐Ÿ—บ๏ธ USDA Zone

Zone 7b

๐Ÿ“† Growing Season

238 days in Somervell County

Growing Tips for Kohlrabi in Somervell County

Direct sow Kohlrabi outdoors after March 19 in Somervell County when soil has warmed and frost danger has passed.

With Somervell County's clay soil (46% clay), work in 3-4 inches of compost before planting Kohlrabi. Avoid tilling when soil is wet to prevent compaction.

Your generous 238.0-day season in Somervell 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 Somervell County, TX?

Somervell County is in Zone 7b with an average last frost of March 19. Plan your Kohlrabi planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Somervell County, TX?

Somervell County, Texas is in USDA Hardiness Zone 7b. The average last spring frost is March 19 and first fall frost is November 12.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Somervell County gardeners in Zone 7b organize planting dates, track what's growing, and never miss a planting window.

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