When to Plant Jicama in Gallatin County, IL
Gallatin County, Illinois gardeners: here's your May plan
Here's what deserves your attention in Gallatin County, Illinois this month. Everything below is tailored to Zone 7a and timed around your local frost dates.
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Fire up the seed-starting tray: jicama
You're about 25 weeks out from your last frost — the perfect window to get these germinating indoors.
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.
Gallatin County, Illinois is in USDA Zone 7a. The average last spring frost is April 6 and the first fall frost is October 30, giving you a growing season of approximately 207 days.
At an elevation of 1,391 feet, Gallatin County receives approximately 37 inches of rainfall annually with predominantly silt loam soil. Summer highs average 85°F, providing good warmth for Jicama during the growing season.
Gallatin County Soil Profile
Soil Type
Silt Loam
Soil pH
6.3-6.8
Drainage
Well Drained
Plant Planting Risk Windows
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 Gallatin County
How your county's soil matches Jicama's growing requirements.
Soil pH
Your soil pH (6.3–6.8) is within Jicama's preferred range (6.0–7.5).
Soil Texture
The silt loam soil in Gallatin County is excellent for Jicama — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is excellent (4.4%) — Jicama will thrive.
How to Plant Jicama
Plant Water Budget
Water stress score is 6/10 — 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 | — | 1.7" | 0" | ❄️ Dormant |
| Feb | — | 1.6" | 0" | ❄️ Dormant |
| Mar | — | 2.7" | 0" | ❄️ Dormant |
| Apr | 4.3" | 3.3" | 1" | 💧 Light watering |
| May | 4.3" | 4.2" | 0.1" | 💧 Light watering |
| Jun | 4.3" | 4.4" | 0" | ✅ Rainfall sufficient |
| Jul | 4.3" | 4.5" | 0" | ✅ Rainfall sufficient |
| Aug | 4.3" | 3.7" | 0.6" | 💧 Light watering |
| Sep | 4.3" | 3.3" | 1" | 💧 Light watering |
| Oct | 4.3" | 2.7" | 1.6" | 💧 Light watering |
| Nov | — | 2.6" | 0" | ❄️ Dormant |
| Dec | — | 2.2" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Gallatin 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 Planting Timeline — Gallatin County, IL
Jicama Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | February 16 | Feb 16 – Mar 2 |
| Transplant Outdoors | April 20 | Apr 20 – May 4 |
| Direct Sow | April 13 | Apr 13 – May 4 |
| Harvest | August 24 | Aug 24 – Nov 2 |
Plant 0.5" deep · 6" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | Start Indoors |
| March | Start Indoors |
| April | Transplant Outdoors Direct Sow |
| May | Transplant Outdoors Direct Sow |
| June | — |
| July | — |
| August | Harvest |
| September | Harvest |
| October | Harvest |
| November | Harvest |
| December | — |
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 7a
📆 Growing Season
207 days in Gallatin County
Growing Tips for Jicama in Gallatin County
Direct sow Jicama outdoors after April 06 in Gallatin 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
Check more plant combinations with our Companion Planting Checker →
Jicama in Other Locations
Frequently Asked Questions
When should I plant Jicama in Gallatin County, IL?
Gallatin County is in Zone 7a with an average last frost of April 6. Plan your Jicama planting based on this frost date — see the calendar above for exact timing.
What planting zone is Gallatin County, IL?
Gallatin County, Illinois is in USDA Hardiness Zone 7a. The average last spring frost is April 6 and first fall frost is October 30.
Your Gallatin County Garden Planner — Free
A 24-page printable planner built for Gallatin 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.