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When to Plant Carrots in Jefferson County, TX

Carrots are a popular root vegetable available in orange, purple, white, and yellow varieties. They are rich in beta-carotene and have a sweet, earthy flavor.

Jefferson County, Texas is in USDA Zone 9a. The average last spring frost is February 13 and the first fall frost is December 6, giving you a growing season of approximately 296 days.

At an elevation of 349 feet, Jefferson County receives approximately 64.9 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 101ยฐF, so Carrots may need afternoon shade and extra watering during peak heat. Sandy soil warms quickly in spring โ€” great for early planting โ€” but Carrots will need more frequent watering and organic matter to retain nutrients. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Carrots root diseases.

Jefferson County, TX (Zone 9a) Year-round
296 days
Last Spring Frost February 13
296 growing days
First Fall Frost December 6

Jefferson County Soil Profile

Soil Type

Sandy Loam

Soil pH

5.4-6.5

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (210 days to spare)
Transplant: Jan 24 🍅 Harvest: Mar 28 – May 2
Recommended (50%) ✓ Fits season (198 days to spare)
Transplant: Feb 13 🍅 Harvest: Apr 17 – May 22
Safe Start (90%) ✓ Fits season (195 days to spare)
Transplant: Mar 6 🍅 Harvest: May 8 – Jun 12

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 Jefferson County

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

Soil pH

Your soil pH (5.4โ€“6.5) is more acidic than Carrots prefers (6.0โ€“6.8). Add garden lime to raise pH.

Soil Texture

Sandy soil in Jefferson County warms quickly in spring but drains fast. Carrots will need more frequent watering and regular compost additions to retain nutrients.

Organic Matter

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

How to Plant Carrots

0.5"
Planting Depth
6"
Between Plants
12"
Between Rows

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

Succession Planting Carrots

5
successive plantings in your 296-day season

Sow every 6.9 weeks. Last sowing by Sep 17 to harvest before frost.

For a dedicated fall crop, sow by Oct 11.

Plant Water Budget

Plant needs
0.8″/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 Carrots

Carrots needs approximately 0.8 inches of water per week (3.5" per month). Here's how your county's rainfall compares month by month.

Month Carrots Needs Rainfall You Supplement Action
Jan โ€” 1.6" 0" โ„๏ธ Dormant
Feb 3.5" 2.1" 1.4" ๐Ÿ’ง Light watering
Mar 3.5" 4.4" 0" โœ… Rainfall sufficient
Apr 3.5" 6.3" 0" โœ… Rainfall sufficient
May 3.5" 9.8" 0" โœ… Rainfall sufficient
Jun 3.5" 10.7" 0" โœ… Rainfall sufficient
Jul 3.5" 8.8" 0" โœ… Rainfall sufficient
Aug 3.5" 6.6" 0" โœ… Rainfall sufficient
Sep 3.5" 6.6" 0" โœ… Rainfall sufficient
Oct 3.5" 4.4" 0" โœ… Rainfall sufficient
Nov 3.5" 2.1" 1.4" ๐Ÿ’ง Light watering
Dec 3.5" 1.6" 1.9" ๐Ÿšฟ Regular watering

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

Carrots 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.

Carrots needs ~1,802 GDD — county provides 7,647 GDD Excellent fit

Carrots Planting Timeline โ€” Jefferson County, TX

Carrots Planting Calendar

Activity When Date Range
Direct Sow January 23 Jan 23 โ€“ Feb 13
Harvest March 27 Mar 27 โ€“ May 1
Fall Sowing October 11 Oct 11 โ€“ Oct 25

Plant 0.5" deep ยท 6" apart ยท Rows 12" apart

Month-by-Month Timeline

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

Growing Conditions

โ˜€๏ธ Sun

Full Sun (6-8+ hours)

๐Ÿ’ง Water

0.8"/week ยท Natural rainfall sufficient

๐Ÿ“… Days to Maturity

60โ€“80 days

๐Ÿงช Soil pH

Needs 6โ€“6.8 ยท Your soil: too_acidic

๐Ÿ—บ๏ธ USDA Zone

Zone 9a

๐Ÿ“† Growing Season

296 days in Jefferson County

Growing Tips for Carrots in Jefferson County

Direct sow Carrots outdoors after February 13 in Jefferson County when soil has warmed and frost danger has passed.

Sandy soil in Jefferson County dries quickly โ€” mulch Carrots with 2-3 inches of straw and water deeply 2-3 times per week rather than lightly every day.

With summer highs reaching 101ยฐF in Jefferson County, provide afternoon shade for Carrots and water deeply in the morning.

Common pests for Carrots in this region include carrot rust fly and parsleyworm. Use row covers early in the season and inspect plants weekly.

General growing tips

Sow seeds directly in loose, stone-free soil for straight roots. Keep soil moist until germination which can take 2-3 weeks. Thin seedlings to 2 inches apart.

Companion Planting

Good Companions

Avoid Planting Near

  • Dill
  • Parsnip

Check more plant combinations with our Companion Planting Checker →

๐ŸŒพ Save Your Own Carrots Seeds
Life Cycle Biennial
Pollination Cross-Pollinated (insects)
How to Collect Replant roots for 2nd year flowers. Harvest umbels when brown.
Storage Store airtight; viable 3 years at 35ยฐF, under 50% humidity.

Isolate 1/2 mile from Queen Anne's Lace (wild carrot). Biennial โ€” requires two seasons.

Frequently Asked Questions

When should I plant Carrots in Jefferson County, TX?

Jefferson County is in Zone 9a with an average last frost of February 13. Plan your Carrots planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Jefferson County, TX?

Jefferson County, Texas is in USDA Hardiness Zone 9a. The average last spring frost is February 13 and first fall frost is December 6.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Jefferson County gardeners in Zone 9a 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 Jefferson County, TX. Local conditions may vary. Last updated: April 2026.