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When to Plant Jicama in Mercer County, WV

Mercer County, West Virginia Zone 7a May

Your May planting checklist for Mercer County, West Virginia

Each item below is timed to Mercer County, West Virginia's frost dates and soil temperatures. Skip nothing, stress about nothing.

Avg. last frost May 7
Avg. first frost October 10
Soil temp (4") 61°F
Watering Moderate
Pest pressure Low
Daylight 14 hrs
  1. Transplant jicama outside

    Pinch off the lowest leaves on each seedling before you plant — it reduces water loss while the roots catch up.

  2. Outdoor sowing time: jicama

    Succession planting is the secret here. Put in a row now, another in 2 weeks, a third in 4.

Get ahead of June
  • Starting indoors: 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.

Mercer County, West Virginia is in USDA Zone 7a. The average last spring frost is May 7 and the first fall frost is October 10, giving you a growing season of approximately 156 days.

At an elevation of 1,135 feet, Mercer County receives approximately 42.8 inches of rainfall annually with predominantly silt loam soil. Summer highs average 85°F, providing good warmth for Jicama during the growing season.

Mercer County, WV (Zone 7a) Moderate season
156 days
Last Spring Frost May 7
156 growing days
First Fall Frost October 10
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Mercer County Soil Profile

Soil Type

Silt Loam

Soil pH

5.5-6.9

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✗ May not fit
Start indoors: Mar 13 Transplant: May 15 🍅 Harvest: Sep 18 – Nov 27
Recommended (50%) ✗ May not fit
Start indoors: Mar 19 Transplant: May 21 🍅 Harvest: Sep 24 – Dec 3
Safe Start (90%) ✗ May not fit
Start indoors: Apr 3 Transplant: Jun 5 🍅 Harvest: Oct 9 – Dec 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 Mercer County

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

Soil pH

Your soil pH (5.5–6.9) overlaps with Jicama's range (6.0–7.5), though not a perfect match.

Soil Texture

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

Organic Matter

Organic matter is moderate (3.3%). 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
1.2″/week
Watering frequency Natural rainfall sufficient
Season total 0 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 3.6" 0" ❄️ Dormant
Feb 3.8" 0" ❄️ Dormant
Mar 4.5" 0" ❄️ Dormant
Apr 3" 0" ❄️ Dormant
May 4.3" 3" 1.3" 💧 Light watering
Jun 4.3" 4.3" 0" ✅ Rainfall sufficient
Jul 4.3" 3.9" 0.4" 💧 Light watering
Aug 4.3" 3.9" 0.4" 💧 Light watering
Sep 4.3" 3" 1.3" 💧 Light watering
Oct 4.3" 2.6" 1.7" 💧 Light watering
Nov 3.2" 0" ❄️ Dormant
Dec 3.9" 0" ❄️ Dormant

Water needs are for active growing months only (May–Oct in Mercer 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 ~2,062 GDD — county provides 2,145 GDD Good fit

Jicama Planting Timeline — Mercer County, WV

Jicama Planting Calendar

Activity When Date Range
Start Indoors March 19 Mar 19 – Apr 2
Transplant Outdoors May 21 May 21 – Jun 4
Direct Sow May 14 May 14 – Jun 4
Harvest September 24 Sep 24 – Dec 3

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

Month-by-Month Timeline

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

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

1"/week · Natural rainfall sufficient

📅 Days to Maturity

120–180 days

🧪 Soil pH

Needs 6–7.5 · Your soil: acceptable

🗺️ USDA Zone

Zone 7a

📆 Growing Season

156 days in Mercer County

Growing Tips for Jicama in Mercer County

Direct sow Jicama outdoors after May 07 in Mercer County when soil has warmed and frost danger has passed.

Your 156.0-day growing season in Mercer County is tight for Jicama (120.0-180.0 days to maturity). Start indoors and choose early-maturing varieties.

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 Mercer County, WV?

Mercer County is in Zone 7a with an average last frost of May 7. Plan your Jicama planting based on this frost date — see the calendar above for exact timing.

What planting zone is Mercer County, WV?

Mercer County, West Virginia is in USDA Hardiness Zone 7a. The average last spring frost is May 7 and first fall frost is October 10.

🌱

Your Mercer County Garden Planner — Free

A 24-page printable planner built for Mercer County (Zone 7a). 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 Mercer County, WV. 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.