When to Plant Jicama in Madison County, IL
Your May game plan for Madison County, Illinois
May is a pivotal month for Madison County, Illinois gardens. Focus on these tasks first and you'll set up the rest of the season for success.
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Time to start jicama inside
Bottom-water once the first true leaves appear — it keeps stems dry and knocks back damping-off.
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.
Madison County, Illinois is in USDA Zone 7a. The average last spring frost is April 11 and the first fall frost is October 22, giving you a growing season of approximately 194 days.
At an elevation of 963 feet, Madison County receives approximately 36.8 inches of rainfall annually with predominantly silt loam soil. Summer highs average 89°F, providing good warmth for Jicama during the growing season.
Madison County Soil Profile
Soil Type
Silt Loam
Soil pH
5.8-6.9
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 Madison County
How your county's soil matches Jicama's growing requirements.
Soil pH
Your soil pH (5.8–6.9) overlaps with Jicama's range (6.0–7.5), though not a perfect match.
Soil Texture
The silt loam soil in Madison County is excellent for Jicama — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is excellent (4.8%) — 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 | — | 1.3" | 0" | ❄️ Dormant |
| Feb | — | 1.5" | 0" | ❄️ Dormant |
| Mar | — | 2.4" | 0" | ❄️ Dormant |
| Apr | 4.3" | 4" | 0.3" | 💧 Light watering |
| May | 4.3" | 3.6" | 0.7" | 💧 Light watering |
| Jun | 4.3" | 5" | 0" | ✅ Rainfall sufficient |
| Jul | 4.3" | 4.1" | 0.2" | 💧 Light watering |
| Aug | 4.3" | 4.1" | 0.2" | 💧 Light watering |
| Sep | 4.3" | 3.4" | 0.9" | 💧 Light watering |
| Oct | 4.3" | 2.8" | 1.5" | 💧 Light watering |
| Nov | — | 2.8" | 0" | ❄️ Dormant |
| Dec | — | 1.7" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Madison 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 — Madison County, IL
Jicama Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | February 21 | Feb 21 – Mar 7 |
| Transplant Outdoors | April 25 | Apr 25 – May 9 |
| Direct Sow | April 18 | Apr 18 – May 9 |
| Harvest | August 29 | Aug 29 – Nov 7 |
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: acceptable
🗺️ USDA Zone
Zone 7a
📆 Growing Season
194 days in Madison County
Growing Tips for Jicama in Madison County
Direct sow Jicama outdoors after April 11 in Madison 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 Madison County, IL?
Madison County is in Zone 7a with an average last frost of April 11. Plan your Jicama planting based on this frost date — see the calendar above for exact timing.
What planting zone is Madison County, IL?
Madison County, Illinois is in USDA Hardiness Zone 7a. The average last spring frost is April 11 and first fall frost is October 22.
Your Madison County Garden Planner — Free
A 24-page printable planner built for Madison 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.