Blog

When to Plant Turnip in Comal County, TX

Turnips are a fast-growing cool-season root vegetable with edible roots and greens. Baby turnips are sweet and tender while mature ones are more pungent.

Comal County, Texas is in USDA Zone 8b. The average last spring frost is March 6 and the first fall frost is November 22, giving you a growing season of approximately 261 days.

At an elevation of 1,346 feet, Comal County receives approximately 58.6 inches of rainfall annually with predominantly clay soil. Summer highs average 91ยฐF, providing good warmth for Turnip during the growing season. Clay soil retains moisture well for Turnip, but amend with compost to improve drainage and prevent root rot. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Turnip root diseases.

Comal County, TX (Zone 8b) Long season
261 days
Last Spring Frost March 6
261 growing days
First Fall Frost November 22

Comal County Soil Profile

Soil Type

Clay

Soil pH

6.7-7.7

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (186 days to spare)
Transplant: Feb 24 🍅 Harvest: Apr 7 – May 12
Recommended (50%) ✓ Fits season (184 days to spare)
Transplant: Mar 6 🍅 Harvest: Apr 17 – May 22
Safe Start (90%) ✓ Fits season (176 days to spare)
Transplant: Apr 2 🍅 Harvest: May 14 – Jun 18

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 Comal County

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

Soil pH

Your soil pH (6.7โ€“7.7) is more alkaline than Turnip prefers (6.0โ€“7.0). Add sulfur or peat moss to lower pH.

Soil Texture

Heavy clay soil (47% clay) in Comal County compacts easily and drains slowly. Amend with compost and avoid working soil when wet.

Drainage

Drainage is adequate for Turnip.

Organic Matter

Organic matter is moderate (3.3%). Annual compost additions will help Turnip.

How to Plant Turnip

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 Turnip

7
successive plantings in your 261-day season

Sow every 4.6 weeks. Last sowing by Sep 23 to harvest before frost.

For a dedicated fall crop, sow by Sep 13.

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
0.9″/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 Turnip

Turnip needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.

Month Turnip Needs Rainfall You Supplement Action
Jan โ€” 1.2" 0" โ„๏ธ Dormant
Feb โ€” 2.1" 0" โ„๏ธ Dormant
Mar 4.3" 3.8" 0.5" ๐Ÿ’ง Light watering
Apr 4.3" 6.6" 0" โœ… Rainfall sufficient
May 4.3" 9.4" 0" โœ… Rainfall sufficient
Jun 4.3" 9.9" 0" โœ… Rainfall sufficient
Jul 4.3" 6.6" 0" โœ… Rainfall sufficient
Aug 4.3" 6.4" 0" โœ… Rainfall sufficient
Sep 4.3" 4.9" 0" โœ… Rainfall sufficient
Oct 4.3" 3.9" 0.4" ๐Ÿ’ง Light watering
Nov 4.3" 2" 2.3" ๐Ÿšฟ Regular watering
Dec โ€” 1.6" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Marโ€“Nov in Comal County). Supplement amounts are based on average rainfall โ€” actual needs vary with temperature, soil, and mulching.

Turnip 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.

Turnip needs ~912 GDD — county provides 4,763 GDD Excellent fit

Turnip Planting Timeline โ€” Comal County, TX

Turnip Planting Calendar

Activity When Date Range
Direct Sow February 20 Feb 20 โ€“ Mar 13
Harvest April 3 Apr 3 โ€“ May 8
Fall Sowing September 13 Sep 13 โ€“ Sep 27

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

Month-by-Month Timeline

MonthActivities
January โ€”
February Direct Sow
March Direct Sow
April Harvest
May Harvest
June โ€”
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

1"/week ยท Natural rainfall sufficient

๐Ÿ“… Days to Maturity

40โ€“60 days

๐Ÿงช Soil pH

Needs 6โ€“7 ยท Your soil: too_alkaline

๐Ÿ—บ๏ธ USDA Zone

Zone 8b

๐Ÿ“† Growing Season

261 days in Comal County

Growing Tips for Turnip in Comal County

Direct sow Turnip outdoors after March 06 in Comal County when soil has warmed and frost danger has passed.

With Comal County's clay soil (47% clay), work in 3-4 inches of compost before planting Turnip. Avoid tilling when soil is wet to prevent compaction.

Your generous 261.0-day season in Comal County allows multiple plantings of Turnip. Sow every 20.0 days for continuous harvest.

Common pests for Turnip 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 early spring or late summer. Harvest when roots are 2-3 inches in diameter for best flavor. Both the roots and the greens are nutritious and edible.

Companion Planting

Good Companions

Avoid Planting Near

  • Potatoes

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Turnip in Comal County, TX?

Comal County is in Zone 8b with an average last frost of March 6. Plan your Turnip planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Comal County, TX?

Comal County, Texas is in USDA Hardiness Zone 8b. The average last spring frost is March 6 and first fall frost is November 22.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Comal County gardeners in Zone 8b organize planting dates, track what's growing, and never miss a planting window.

Get Your Free Garden Planner →

Free download. Plan your entire garden season in minutes.

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