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When to Plant Jicama in Refugio County, TX

Refugio County, Texas Zone 9b May

Top priorities for Refugio County, Texas gardeners in May

May rewards gardeners who work with the weather, not against it. Here's how to stay in step this month in Refugio County, Texas.

Avg. last frost February 16
Avg. first frost December 6
Soil temp (4") 76°F
Watering Low
Pest pressure High
Daylight 13.4 hrs
Coming up in June — start thinking about
  • First harvests: jicama

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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.

Refugio County, Texas is in USDA Zone 9b. The average last spring frost is February 16 and the first fall frost is December 6, giving you a growing season of approximately 293 days.

At an elevation of 1,000 feet, Refugio County receives approximately 68.4 inches of rainfall annually with predominantly loam soil. Summer highs average 103°F, so Jicama may need afternoon shade and extra watering during peak heat. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Jicama root diseases.

Refugio County, TX (Zone 9b) Year-round
293 days
Last Spring Frost February 16
293 growing days
First Fall Frost December 6
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Refugio County Soil Profile

Soil Type

Loam

Soil pH

6.7-7.2

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (97 days to spare)
Start indoors: Dec 22 Transplant: Feb 9 🍅 Harvest: Jun 15 – Aug 24
Recommended (50%) ✓ Fits season (90 days to spare)
Start indoors: Jan 5 Transplant: Feb 23 🍅 Harvest: Jun 29 – Sep 7
Safe Start (90%) ✓ Fits season (82 days to spare)
Start indoors: Jan 29 Transplant: Mar 19 🍅 Harvest: Jul 23 – Oct 1

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 Refugio County

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

Soil pH

Your soil pH (6.7–7.2) is within Jicama's preferred range (6.0–7.5).

Soil Texture

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

Organic Matter

Organic matter is moderate (2.0%). Annual compost additions will help 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
0.0″/week
Watering frequency Only during dry spells
Season total 60 gal / 100 sq ft

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 2" 0" ❄️ Dormant
Feb 4.3" 2.1" 2.2" 🚿 Regular watering
Mar 4.3" 3.9" 0.4" 💧 Light watering
Apr 4.3" 8.3" 0" ✅ Rainfall sufficient
May 4.3" 9.2" 0" ✅ Rainfall sufficient
Jun 4.3" 11.3" 0" ✅ Rainfall sufficient
Jul 4.3" 9.3" 0" ✅ Rainfall sufficient
Aug 4.3" 8" 0" ✅ Rainfall sufficient
Sep 4.3" 5.7" 0" ✅ Rainfall sufficient
Oct 4.3" 4.5" 0" ✅ Rainfall sufficient
Nov 4.3" 2.4" 1.9" 💧 Light watering
Dec 4.3" 1.8" 2.5" 🚿 Regular watering

Water needs are for active growing months only (Feb–Dec in Refugio County). Supplement amounts are based on average rainfall — 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" — 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.

Jicama needs ~4,088 GDD — county provides 8,011 GDD Excellent fit

Jicama Planting Timeline — Refugio County, TX

Jicama Planting Calendar

Activity When Date Range
Start Indoors January 5 Jan 5 – Jan 19
Transplant Outdoors February 23 Feb 23 – Mar 9
Direct Sow February 16 Feb 16 – Mar 9
Harvest June 29 Jun 29 – Sep 7

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

Month-by-Month Timeline

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

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

1"/week · Only during dry spells

📅 Days to Maturity

120–180 days

🧪 Soil pH

Needs 6–7.5 · Your soil: ideal

🗺️ USDA Zone

Zone 9b

📆 Growing Season

293 days in Refugio County

Growing Tips for Jicama in Refugio County

Direct sow Jicama outdoors after February 16 in Refugio County when soil has warmed and frost danger has passed.

With summer highs reaching 103°F in Refugio County, provide afternoon shade for Jicama and water deeply in the morning.

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 Refugio County, TX?

Refugio County is in Zone 9b with an average last frost of February 16. Plan your Jicama planting based on this frost date — see the calendar above for exact timing.

What planting zone is Refugio County, TX?

Refugio County, Texas is in USDA Hardiness Zone 9b. The average last spring frost is February 16 and first fall frost is December 6.

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Your Refugio County Garden Planner — Free

A 24-page printable planner built for Refugio County (Zone 9b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.

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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 Refugio 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.