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When to plant Eggplant in Piatt County, IL

Piatt County sits in USDA Zone 6a. Plant Eggplant between April 21 (after last frost on April 14) and May 12.

When to Plant Eggplant in Piatt County, IL

Eggplant

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.

Piatt County, Illinois is in USDA Zone 6a. The average last spring frost is April 14 and the first fall frost is October 16, giving you a growing season of approximately 185 days.

At an elevation of 1,118 feet, Piatt County receives approximately 38.8 inches of rainfall annually with predominantly silt loam soil. Summer highs average 83°F, so choose short-season varieties of Eggplant to ensure they mature before fall.

Piatt County, IL (Zone 6a) Moderate season
185 days
Last Spring Frost April 14
185 growing days
First Fall Frost October 16

Piatt County Soil Profile

Soil Type

Silt Loam

Soil pH

6-7.1

Drainage

Well Drained

How Much Eggplant to Grow

4-6 lbs
Average yield per plant
2
Plants per person
4 sq ft
Space per person

For a family of 4, plant approximately 8 eggplant plants in about 16 sq ft. In Piatt County's 185-day season, you'll have plenty of time for a full harvest. Plan your garden layout →

Monthly Watering Guide for Eggplant

Eggplant needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.

Month Eggplant Needs Rainfall You Supplement Action
Jan 1.6" 0" ❄️ Dormant
Feb 1.8" 0" ❄️ Dormant
Mar 2.9" 0" ❄️ Dormant
Apr 4.3" 4.2" 0.1" 💧 Light watering
May 4.3" 4.7" 0" ✅ Rainfall sufficient
Jun 4.3" 4.6" 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 Piatt County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.

Eggplant Planting Timeline — Piatt County, IL

Eggplant Planting Calendar

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

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

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

Moderate — regular watering

📅 Days to Maturity

65–85 days

🧪 Soil pH

Needs 5.5–7 · Your soil: N/A

🗺️ USDA Zone

Zone 6a

📆 Growing Season

185 days in Piatt County

Growing Tips for Piatt 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

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Eggplant in Piatt County, IL?

Piatt County is in Zone 6a with an average last frost of April 14. Plan your Eggplant planting based on this frost date — see the calendar above for exact timing.

What planting zone is Piatt County, IL?

Piatt County, Illinois is in USDA Hardiness Zone 6a. The average last spring frost is April 14 and first fall frost is October 16.

When should I plant Eggplant in Piatt County, IL?

In Piatt County, IL, plant Eggplant after the last frost (around April 14) and before the first frost (around October 16). Best results when soil holds above 50°F.

What growing zone is Piatt County, IL for Eggplant?

Piatt County sits in USDA Zone 6a. Eggplant grows reliably in zones 5a through 11b, so it's a good fit here.

Can Eggplant grow in Piatt County's climate?

Yes — Eggplant grows well in Piatt County's temperate climate. Piatt County averages a 185-day frost-free season, with last frost around April 14 and first frost around October 16.

🌱

Your Piatt County Garden Planner — Free

A 22-page printable planner built for Piatt County (Zone 6a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.

Instant PDF download. No spam, unsubscribe any time.

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

Sources & credits

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