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When to Plant Eggplant in Ferry County, WA

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.

Ferry County, Washington is in USDA Zone 5b. The average last spring frost is May 10 and the first fall frost is September 24, giving you a growing season of approximately 137 days.

At an elevation of 3,990 feet, Ferry County receives approximately 18.2 inches of rainfall annually with predominantly silt loam soil. Summer highs average 84ยฐF, so choose short-season varieties of Eggplant to ensure they mature before fall. With low rainfall, drip irrigation is essential for growing Eggplant successfully. Mulch heavily to conserve soil moisture.

Ferry County, WA (Zone 5b) Short season
137 days
Last Spring Frost May 10
137 growing days
First Fall Frost September 24

Ferry County Soil Profile

Soil Type

Silt Loam

Soil pH

5.6-6.4

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✗ May not fit
Start indoors: Feb 21 Transplant: May 16 🍅 Harvest: Jul 25 – Sep 26
Recommended (50%) ✗ May not fit
Start indoors: Mar 1 Transplant: May 24 🍅 Harvest: Aug 2 – Oct 4
Safe Start (90%) ✗ May not fit
Start indoors: Mar 20 Transplant: Jun 12 🍅 Harvest: Aug 21 – Oct 23

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
0.6″/week
You supply
0.7″/week
Watering frequency 2-3 times/week
Season total 905 gal / 100 sq ft
Eggplant needs ~975 GDD — county provides 1,781 GDD Excellent fit

Eggplant Planting Timeline โ€” Ferry County, WA

Eggplant Planting Calendar

Activity When Date Range
Start Indoors March 1 Mar 1 โ€“ Mar 15
Transplant Outdoors May 24 May 24 โ€“ Jun 7
Direct Sow May 17 May 17 โ€“ Jun 7
Harvest August 2 Aug 2 โ€“ Oct 4

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

Month-by-Month Timeline

MonthActivities
January โ€”
February โ€”
March Start Indoors
April โ€”
May Transplant Outdoors Direct Sow
June Transplant Outdoors Direct Sow
July โ€”
August Harvest
September Harvest
October Harvest
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 5b

Growing Season

137 days

Growing Tips for Ferry 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 Ferry County, WA?

Ferry County is in Zone 5b with an average last frost of May 10. Plan your Eggplant planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Ferry County, WA?

Ferry County, Washington is in USDA Hardiness Zone 5b. The average last spring frost is May 10 and first fall frost is September 24.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Ferry County gardeners in Zone 5b organize planting dates, track what's growing, and never miss a planting window.

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