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When to Plant Eggplant in Franklin County, WA

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.

Franklin County, Washington is in USDA Zone 7a. The average last spring frost is April 13 and the first fall frost is October 23, giving you a growing season of approximately 193 days.

At an elevation of 1,556 feet, Franklin County receives approximately 15.7 inches of rainfall annually with predominantly silt loam soil. Summer highs average 90°F, providing good warmth for Eggplant during the growing season. With low rainfall, drip irrigation is essential for growing Eggplant successfully. Mulch heavily to conserve soil moisture.

Franklin County, WA (Zone 7a) Moderate season
193 days
Last Spring Frost April 13
193 growing days
First Fall Frost October 23

Franklin County Soil Profile

Soil Type

Silt Loam

Soil pH

6.0-7.0

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 Franklin County's 193-day season, you'll have plenty of time for a full harvest. Plan your garden layout →

Eggplant Planting Timeline — Franklin County, WA

Eggplant Planting Calendar

Activity When Date Range
Start Indoors February 9 Feb 9 – Feb 23
Transplant Outdoors April 27 Apr 27 – May 11
Direct Sow April 20 Apr 20 – May 11
Harvest July 6 Jul 6 – Sep 7

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 7a

📆 Growing Season

193 days in Franklin County

Growing Tips for Franklin 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 Franklin County, WA?

Franklin County is in Zone 7a with an average last frost of April 13. Plan your Eggplant planting based on this frost date — see the calendar above for exact timing.

What planting zone is Franklin County, WA?

Franklin County, Washington is in USDA Hardiness Zone 7a. The average last spring frost is April 13 and first fall frost is October 23.

🌱

Your Franklin County Garden Planner — Free

A 22-page printable planner built for Franklin 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.

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 Franklin County, WA. Local conditions may vary. Last updated: June 2026.

Sources & credits

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