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When to Plant Jicama in DeWitt County, TX

Jicama is a tropical legume grown for its crisp, sweet, starchy root. It requires a very long, warm growing season but produces a refreshing, water chestnut-like tuber.

DeWitt County, Texas is in USDA Zone 8b. The average last spring frost is March 2 and the first fall frost is November 26, giving you a growing season of approximately 269 days.

At an elevation of 1,649 feet, DeWitt County receives approximately 62.1 inches of rainfall annually with predominantly loam soil. Summer highs average 91ยฐF, providing good warmth for Jicama during the growing season. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Jicama root diseases.

DeWitt County, TX (Zone 8b) Long season
269 days
Last Spring Frost March 2
269 growing days
First Fall Frost November 26

DeWitt County Soil Profile

Soil Type

Loam

Soil pH

6.8-7.8

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (60 days to spare)
Start indoors: Dec 31 Transplant: Mar 4 🍅 Harvest: Jul 8 – Sep 16
Recommended (50%) ✓ Fits season (59 days to spare)
Start indoors: Jan 12 Transplant: Mar 16 🍅 Harvest: Jul 20 – Sep 28
Safe Start (90%) ✓ Fits season (53 days to spare)
Start indoors: Feb 4 Transplant: Apr 8 🍅 Harvest: Aug 12 – Oct 21

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 DeWitt County

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

Soil pH

Your soil pH (6.8โ€“7.8) overlaps with Jicama's range (6.0โ€“7.5), though not a perfect match.

Soil Texture

The loam soil in DeWitt County is excellent for Jicama โ€” good drainage, moisture retention, and nutrient holding capacity.

Drainage

Drainage is adequate for Jicama.

Organic Matter

Organic matter is low (1.9%). Add 2-3 inches of compost before planting Jicama.

How to Plant Jicama

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

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
1.0″/week
You supply
0.4″/week
Watering frequency 1-2 times/week
Season total 949 gal / 100 sq ft
Drought risk

Water stress score is 6/10 โ€” consider drought-tolerant varieties and mulching

Monthly Watering Guide for Jicama

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

Month Jicama Needs Rainfall You Supplement Action
Jan โ€” 1.8" 0" โ„๏ธ Dormant
Feb โ€” 2.1" 0" โ„๏ธ Dormant
Mar 4.3" 4" 0.3" ๐Ÿ’ง Light watering
Apr 4.3" 5.9" 0" โœ… Rainfall sufficient
May 4.3" 9.1" 0" โœ… Rainfall sufficient
Jun 4.3" 11.3" 0" โœ… Rainfall sufficient
Jul 4.3" 6.9" 0" โœ… Rainfall sufficient
Aug 4.3" 7.9" 0" โœ… Rainfall sufficient
Sep 4.3" 5.6" 0" โœ… Rainfall sufficient
Oct 4.3" 3.7" 0.6" ๐Ÿ’ง Light watering
Nov 4.3" 2.3" 2" ๐Ÿ’ง Light watering
Dec โ€” 1.5" 0" โ„๏ธ Dormant

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

Jicama 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.

Jicama needs ~2,738 GDD — county provides 4,909 GDD Excellent fit

Jicama Planting Timeline โ€” DeWitt County, TX

Jicama Planting Calendar

Activity When Date Range
Start Indoors January 12 Jan 12 โ€“ Jan 26
Transplant Outdoors March 16 Mar 16 โ€“ Mar 30
Direct Sow March 9 Mar 9 โ€“ Mar 30
Harvest July 20 Jul 20 โ€“ Sep 28

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

Month-by-Month Timeline

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

Growing Conditions

โ˜€๏ธ Sun

Full Sun (6-8+ hours)

๐Ÿ’ง Water

1"/week ยท 1-2 times/week

๐Ÿ“… Days to Maturity

120โ€“180 days

๐Ÿงช Soil pH

Needs 6โ€“7.5 ยท Your soil: acceptable

๐Ÿ—บ๏ธ USDA Zone

Zone 8b

๐Ÿ“† Growing Season

269 days in DeWitt County

Growing Tips for Jicama in DeWitt County

Direct sow Jicama outdoors after March 02 in DeWitt County when soil has warmed and frost danger has passed.

Common pests for Jicama in this region include bean beetles and aphids. Use row covers early in the season and inspect plants weekly.

General growing tips

Start seeds indoors 8-10 weeks before last frost. Pinch off flowers to direct energy to root development. Harvest before first frost when roots are 3-6 inches across.

Companion Planting

Good Companions

Avoid Planting Near

  • Fennel

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Jicama in DeWitt County, TX?

DeWitt County is in Zone 8b with an average last frost of March 2. Plan your Jicama planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is DeWitt County, TX?

DeWitt County, Texas is in USDA Hardiness Zone 8b. The average last spring frost is March 2 and first fall frost is November 26.

๐ŸŒฑ

Plan Your Garden with Confidence

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

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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 DeWitt County, TX. Local conditions may vary. Last updated: April 2026.