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When to plant Eggplant in Greene County, IA

Plant Eggplant in Greene County after April 27; the prime window is May 4–May 25.

When to Plant Eggplant in Greene County, IA

Eggplant
Greene County, Iowa Zone 5a July

Your July game plan for Greene County, Iowa

Here's what deserves your attention in Greene County, Iowa this month. Everything below is tailored to Zone 5a and timed around your local frost dates.

Avg. last frost April 27
Avg. first frost October 5
Soil temp (4") 74°F
Watering Moderate
Pest pressure High
Daylight 14.8 hrs
  1. Sow eggplant in trays indoors

    You're about 13 weeks out from your last frost — the perfect window to get these germinating indoors.

  2. Bring in the eggplant

    Taste as you pick. The first ripe produce is the best feedback loop you'll get all season.

August will be here before you know it — start on
  • First harvests: eggplant

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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.

Greene County, Iowa is in USDA Zone 5a. The average last spring frost is April 27 and the first fall frost is October 5, giving you a growing season of approximately 161 days.

At an elevation of 1,292 feet, Greene County receives approximately 33.7 inches of rainfall annually with predominantly silt loam soil. Summer highs average 86°F, providing good warmth for Eggplant during the growing season.

Greene County, IA (Zone 5a) Moderate season
161 days
Last Spring Frost April 27
161 growing days
First Fall Frost October 5

Greene County Soil Profile

Soil Type

Silt Loam

Soil pH

5.8-6.9

Drainage

Well Drained

Eggplant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (12 days to spare)
Start indoors: Feb 11 Transplant: May 6 🍅 Harvest: Jul 15 – Sep 16
Recommended (50%) ✓ Fits season (14 days to spare)
Start indoors: Feb 16 Transplant: May 11 🍅 Harvest: Jul 20 – Sep 21
Safe Start (90%) ✓ Fits season (12 days to spare)
Start indoors: Mar 2 Transplant: May 25 🍅 Harvest: Aug 3 – Oct 5

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 Greene County

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

Soil pH

Your soil pH (5.8–6.9) is within Eggplant's preferred range (5.5–7.0).

Soil Texture

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

Organic Matter

Organic matter is excellent (4.2%) — Eggplant will thrive.

How to Plant Eggplant

1"
Planting Depth
30"
Between Plants
42"
Between Rows

Succession Planting Eggplant

2
successive plantings in your 161-day season

Sow every 7.4 weeks. Last sowing by Jul 12 to harvest before frost.

Eggplant Water Budget

Plant needs
1.1″/week
Rainfall provides
0.9″/week
You supply
0.2″/week
Watering frequency Only during dry spells
Season total 316 gal / 100 sq ft

Monthly Watering Guide for Eggplant

Eggplant needs approximately 1.1 inches of water per week (4.8" per month). Here's how your county's rainfall compares month by month.

Month Eggplant Needs Rainfall You Supplement Action
Jan 1.3" 0" ❄️ Dormant
Feb 1.4" 0" ❄️ Dormant
Mar 2.7" 0" ❄️ Dormant
Apr 4.8" 3.1" 1.7" 💧 Light watering
May 4.8" 4" 0.8" 💧 Light watering
Jun 4.8" 4.6" 0.2" 💧 Light watering
Jul 4.8" 3.3" 1.5" 💧 Light watering
Aug 4.8" 3.6" 1.2" 💧 Light watering
Sep 4.8" 2.9" 1.9" 💧 Light watering
Oct 4.8" 2.4" 2.4" 🚿 Regular watering
Nov 2.1" 0" ❄️ Dormant
Dec 2.2" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Greene County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.

Eggplant 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.

Eggplant needs ~1,088 GDD — county provides 2,334 GDD Excellent fit

Eggplant Planting Timeline — Greene County, IA

Eggplant Planting Calendar

Activity When Date Range
Start Indoors February 16 Feb 16 – Mar 2
Transplant Outdoors May 11 May 11 – May 25
Direct Sow May 4 May 4 – May 25
Harvest July 20 Jul 20 – Sep 21

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

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

1.1"/week · Only during dry spells

📅 Days to Maturity

65–85 days

🧪 Soil pH

Needs 5.5–7 · Your soil: ideal

🗺️ USDA Zone

Zone 5a

📆 Growing Season

161 days in Greene County

Growing Tips for Eggplant in Greene County

Direct sow Eggplant outdoors after April 27 in Greene County when soil has warmed and frost danger has passed.

Common pests for Eggplant in this region include tomato hornworm 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. 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 Greene County, IA?

Greene County is in Zone 5a with an average last frost of April 27. Plan your Eggplant planting based on this frost date — see the calendar above for exact timing.

What planting zone is Greene County, IA?

Greene County, Iowa is in USDA Hardiness Zone 5a. The average last spring frost is April 27 and first fall frost is October 5.

When should I plant Eggplant in Greene County, IA?

In Greene County, IA, plant Eggplant after the last frost (around April 27) and before the first frost (around October 5). Best results when soil holds above 50°F.

What growing zone is Greene County, IA for Eggplant?

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

Can Eggplant grow in Greene County's climate?

Yes — Eggplant grows well in Greene County's temperate climate. Greene County averages a 161-day frost-free season, with last frost around April 27 and first frost around October 5.

🌱

Your Greene County Garden Planner — Free

A 22-page printable planner built for Greene County (Zone 5a). 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 Greene County, IA. Local conditions may vary. Last updated: July 2026.

Sources & credits

Every number on this page traces back to a primary horticulture or government data source. Click through to verify.