Blog

When to Plant Eggplant in Monroe County, IL

Eggplant is a heat-loving solanaceous crop that produces glossy fruits in purple, white, or striped varieties. It requires long, warm growing seasons for best production.

Monroe County, Illinois is in USDA Zone 6b. The average last spring frost is April 14 and the first fall frost is October 24, giving you a growing season of approximately 193 days.

At an elevation of 1,278 feet, Monroe County receives approximately 34.2 inches of rainfall annually with predominantly silt loam soil. Summer highs average 88ยฐF, providing good warmth for Eggplant during the growing season.

Monroe County, IL (Zone 6b) Moderate season
193 days
Last Spring Frost April 14
193 growing days
First Fall Frost October 24

Monroe County Soil Profile

Soil Type

Silt Loam

Soil pH

5.7-6.8

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (47 days to spare)
Start indoors: Jan 26 Transplant: Apr 20 🍅 Harvest: Jun 29 – Aug 31
Recommended (50%) ✓ Fits season (46 days to spare)
Start indoors: Feb 3 Transplant: Apr 28 🍅 Harvest: Jul 7 – Sep 8
Safe Start (90%) ✓ Fits season (48 days to spare)
Start indoors: Feb 14 Transplant: May 9 🍅 Harvest: Jul 18 – Sep 19

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.

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
0.7″/week
You supply
0.3″/week
Watering frequency 1-2 times/week
Season total 527 gal / 100 sq ft
Drought risk

Water stress score is 6/10 โ€” consider drought-tolerant varieties and mulching

Eggplant needs ~1,200 GDD — county provides 3,088 GDD Excellent fit

Eggplant Planting Timeline โ€” Monroe County, IL

Eggplant Planting Calendar

Activity When Date Range
Start Indoors February 3 Feb 3 โ€“ Feb 17
Transplant Outdoors April 28 Apr 28 โ€“ May 12
Direct Sow April 21 Apr 21 โ€“ May 12
Harvest July 7 Jul 7 โ€“ Sep 8

Plant 1" deep ยท 30" apart ยท Rows 42" apart

Month-by-Month Timeline

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

Growing Conditions

Sun

Full Sun (6-8+ hours)

Water

Moderate โ€” regular watering

Days to Maturity

65โ€“85 days

Soil pH

5.5 โ€“ 7

USDA Zone

Zone 6b

Growing Season

193 days

Growing Tips for Monroe County

Start seeds indoors 8-10 weeks before last frost. Transplant only after nighttime temperatures stay above 55F. Mulch to retain moisture and warmth around roots.

Companion Planting

Good Companions

Avoid Planting Near

  • Fennel
  • Kohlrabi

Level Up Your Garden

Frequently Asked Questions

When should I plant Eggplant in Monroe County, IL?

Monroe County is in Zone 6b with an average last frost of April 14. Plan your Eggplant planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Monroe County, IL?

Monroe County, Illinois is in USDA Hardiness Zone 6b. The average last spring frost is April 14 and first fall frost is October 24.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Monroe County gardeners in Zone 6b organize planting dates, track what's growing, and never miss a planting window.

Get Your Free Garden Planner →

Free download. Plan your entire garden season in minutes.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Monroe County, IL. Local conditions may vary. Last updated: April 2026.