Blog

When to Plant Rutabaga in Karnes County, TX

Karnes County, Texas Zone 9a May

What to do in May

Your garden in Karnes County, Texas is working on a schedule, even when you're not. Here's where you should be this May.

Avg. last frost February 26
Avg. first frost November 30
Soil temp (4") 59°F
Watering Low
Pest pressure High
Daylight 13.4 hrs
  1. Collect rutabaga at their peak

    Don't tug. Use scissors or pruners for clean cuts — torn stems invite disease.

June prep starts now
  • First harvests: rutabaga

Instant PDF download. No spam, unsubscribe any time.

Rutabagas are a cross between turnips and cabbage, producing large yellow-fleshed roots with a sweet, mild flavor. They are excellent mashed, roasted, or in stews.

Karnes County, Texas is in USDA Zone 9a. The average last spring frost is February 26 and the first fall frost is November 30, giving you a growing season of approximately 277 days.

At an elevation of 4,532 feet, Karnes County receives approximately 67.2 inches of rainfall annually with predominantly loam soil. Summer highs average 95°F, so Rutabaga may need afternoon shade and extra watering during peak heat. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Rutabaga root diseases.

Karnes County, TX (Zone 9a) Year-round
277 days
Last Spring Frost February 26
277 growing days
First Fall Frost November 30
Share this guide:

Karnes County Soil Profile

Soil Type

Loam

Soil pH

6.3-7.8

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (162 days to spare)
Transplant: Feb 14 🍅 Harvest: May 9 – Jun 13
Recommended (50%) ✓ Fits season (158 days to spare)
Transplant: Feb 26 🍅 Harvest: May 21 – Jun 25
Safe Start (90%) ✓ Fits season (154 days to spare)
Transplant: Mar 23 🍅 Harvest: Jun 15 – Jul 20

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 Karnes County

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

Soil pH

Your soil pH (6.3–7.8) overlaps with Rutabaga's range (6.0–7.5), though not a perfect match.

Soil Texture

The loam soil in Karnes County is excellent for Rutabaga — good drainage, moisture retention, and nutrient holding capacity.

Drainage

Drainage is adequate for Rutabaga.

Organic Matter

Organic matter is moderate (2.2%). Annual compost additions will help Rutabaga.

How to Plant Rutabaga

1"
Planting Depth
15"
Between Plants
24"
Between Rows

Fall planting: Sow 8 weeks before your first frost date for a fall harvest.

Succession Planting Rutabaga

4
successive plantings in your 277-day season

Sow every 9.1 weeks. Last sowing by Aug 22 to harvest before frost.

For a dedicated fall crop, sow by Oct 05.

Plant Water Budget

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

Monthly Watering Guide for Rutabaga

Rutabaga needs approximately 0.7 inches of water per week (3" per month). Here's how your county's rainfall compares month by month.

Month Rutabaga Needs Rainfall You Supplement Action
Jan 1.6" 0" ❄️ Dormant
Feb 3" 2.6" 0.4" 💧 Light watering
Mar 3" 4.6" 0" ✅ Rainfall sufficient
Apr 3" 6.3" 0" ✅ Rainfall sufficient
May 3" 8.6" 0" ✅ Rainfall sufficient
Jun 3" 11.7" 0" ✅ Rainfall sufficient
Jul 3" 9.1" 0" ✅ Rainfall sufficient
Aug 3" 8.7" 0" ✅ Rainfall sufficient
Sep 3" 6.7" 0" ✅ Rainfall sufficient
Oct 3" 3.9" 0" ✅ Rainfall sufficient
Nov 3" 2" 1" 💧 Light watering
Dec 1.5" 0" ❄️ Dormant

Water needs are for active growing months only (Feb–Nov in Karnes County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.

Rutabaga 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.

Rutabaga needs ~1,912 GDD — county provides 5,907 GDD Excellent fit

Rutabaga Planting Timeline — Karnes County, TX

Rutabaga Planting Calendar

Activity When Date Range
Direct Sow February 5 Feb 5 – Feb 26
Harvest April 30 Apr 30 – Jun 4
Fall Sowing October 5 Oct 5 – Oct 19

Plant 1" deep · 15" apart · Rows 24" apart

Month-by-Month Timeline

MonthActivities
January
February Direct Sow
March
April Harvest
May Harvest
June Harvest
July
August
September
October Fall Sowing
November
December
Share this guide:

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

0.7"/week · Natural rainfall sufficient

📅 Days to Maturity

80–100 days

🧪 Soil pH

Needs 6–7.5 · Your soil: acceptable

🗺️ USDA Zone

Zone 9a

📆 Growing Season

277 days in Karnes County

Growing Tips for Rutabaga in Karnes County

Direct sow Rutabaga outdoors after February 26 in Karnes County when soil has warmed and frost danger has passed.

Common pests for Rutabaga 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 summer for fall harvest. Thin seedlings to 6-8 inches apart. Flavor improves significantly after a few light frosts.

Companion Planting

Good Companions

Avoid Planting Near

  • Potatoes

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Rutabaga in Karnes County, TX?

Karnes County is in Zone 9a with an average last frost of February 26. Plan your Rutabaga planting based on this frost date — see the calendar above for exact timing.

What planting zone is Karnes County, TX?

Karnes County, Texas is in USDA Hardiness Zone 9a. The average last spring frost is February 26 and first fall frost is November 30.

🌱

Your Karnes County Garden Planner — Free

A 24-page printable planner built for Karnes County (Zone 9a). 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 Karnes County, TX. 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.