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When to Plant Jicama in Lane County, OR

Lane County, Oregon Zone 8b May

Your May game plan for Lane County, Oregon

Welcome to May in Zone 8b. These are the moves that will have the biggest impact on your growing season.

Avg. last frost April 21
Avg. first frost October 25
Soil temp (4") 70°F
Watering High
Pest pressure High
Daylight 14.6 hrs
  1. Set out jicama seedlings

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

To set up a strong June, finish these tasks
  • 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.

Lane County, Oregon is in USDA Zone 8b. The average last spring frost is April 21 and the first fall frost is October 25, giving you a growing season of approximately 187 days.

At an elevation of 48 feet, Lane County receives approximately 50.6 inches of rainfall annually with predominantly silt loam soil. Summer highs average 81°F, so choose short-season varieties of Jicama to ensure they mature before fall. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Jicama root diseases.

Lane County, OR (Zone 8b) Moderate season
187 days
Last Spring Frost April 21
187 growing days
First Fall Frost October 25

Lane County Soil Profile

Soil Type

Silt Loam

Soil pH

5.7-6.4

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✗ May not fit
Start indoors: Feb 23 Transplant: Apr 27 🍅 Harvest: Aug 31 – Nov 9
Recommended (50%) ✗ May not fit
Start indoors: Mar 3 Transplant: May 5 🍅 Harvest: Sep 8 – Nov 17
Safe Start (90%) ✗ May not fit
Start indoors: Mar 23 Transplant: May 25 🍅 Harvest: Sep 28 – Dec 7

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 Lane County

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

Soil pH

Your soil pH (5.7–6.4) overlaps with Jicama's range (6.0–7.5), though not a perfect match.

Soil Texture

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

Organic Matter

Organic matter is excellent (4.3%) — Jicama will thrive.

How to Plant Jicama

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

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
1.1″/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 7.6" 0" ❄️ Dormant
Feb 5.3" 0" ❄️ Dormant
Mar 5.3" 0" ❄️ Dormant
Apr 4.3" 4" 0.3" 💧 Light watering
May 4.3" 2.5" 1.8" 💧 Light watering
Jun 4.3" 1.6" 2.7" 🚿 Regular watering
Jul 4.3" 0.8" 3.5" 🚿 Regular watering
Aug 4.3" 0.9" 3.4" 🚿 Regular watering
Sep 4.3" 2" 2.3" 🚿 Regular watering
Oct 4.3" 4.3" 0" ✅ Rainfall sufficient
Nov 8.3" 0" ❄️ Dormant
Dec 8" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Lane 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 ~1,612 GDD — county provides 2,010 GDD Good fit

Jicama Planting Timeline — Lane County, OR

Jicama Planting Calendar

Activity When Date Range
Start Indoors March 3 Mar 3 – Mar 17
Transplant Outdoors May 5 May 5 – May 19
Direct Sow April 28 Apr 28 – May 19
Harvest September 8 Sep 8 – Nov 17

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

Month-by-Month Timeline

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

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 8b

📆 Growing Season

187 days in Lane County

Growing Tips for Jicama in Lane County

Direct sow Jicama outdoors after April 21 in Lane County when soil has warmed and frost danger has passed.

Your 187.0-day growing season in Lane 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 Lane County, OR?

Lane County is in Zone 8b with an average last frost of April 21. Plan your Jicama planting based on this frost date — see the calendar above for exact timing.

What planting zone is Lane County, OR?

Lane County, Oregon is in USDA Hardiness Zone 8b. The average last spring frost is April 21 and first fall frost is October 25.

🌱

Your Lane County Garden Planner — Free

A 24-page printable planner built for Lane County (Zone 8b). 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 Lane County, OR. 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.