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When to Plant Parsnip in Asotin County, WA

Parsnips are a sweet, nutty root vegetable that develops best flavor after exposure to frost. They require a long growing season but reward patient gardeners.

Asotin County, Washington is in USDA Zone 6b. The average last spring frost is May 9 and the first fall frost is September 30, giving you a growing season of approximately 144 days.

At an elevation of 2,029 feet, Asotin County receives approximately 14 inches of rainfall annually with predominantly silt loam soil. Summer highs average 85ยฐF, providing good warmth for Parsnip during the growing season. With low rainfall, drip irrigation is essential for growing Parsnip successfully. Mulch heavily to conserve soil moisture.

Asotin County, WA (Zone 6b) Short season
144 days
Last Spring Frost May 9
144 growing days
First Fall Frost September 30

Asotin County Soil Profile

Soil Type

Silt Loam

Soil pH

5.5-6.5

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✗ May not fit
Transplant: Apr 28 🍅 Harvest: Aug 11 – Sep 22
Recommended (50%) ✗ May not fit
Transplant: May 9 🍅 Harvest: Aug 22 – Oct 3
Safe Start (90%) ✗ May not fit
Transplant: Jun 6 🍅 Harvest: Sep 19 – Oct 31

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
0.4″/week
You supply
0.6″/week
Watering frequency 1-2 times/week
Season total 758 gal / 100 sq ft
Parsnip needs ~1,581 GDD — county provides 1,980 GDD Good fit

Parsnip Planting Timeline โ€” Asotin County, WA

Parsnip Planting Calendar

Activity When Date Range
Direct Sow April 25 Apr 25 โ€“ May 16
Fall Sowing July 22 Jul 22 โ€“ Aug 5
Harvest August 8 Aug 8 โ€“ Sep 19

Plant 1" deep ยท 15" apart ยท Rows 24" apart

Month-by-Month Timeline

MonthActivities
January โ€”
February โ€”
March โ€”
April Direct Sow
May Direct Sow
June โ€”
July Fall Sowing
August Fall Sowing 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

100โ€“130 days

Soil pH

6 โ€“ 7

USDA Zone

Zone 6b

Growing Season

144 days

Growing Tips for Asotin County

Use only fresh seed as parsnip seed viability declines rapidly. Sow directly in spring in deeply worked soil. Leave roots in the ground through winter for sweetest flavor.

Companion Planting

Good Companions

Avoid Planting Near

  • Carrots
  • Celery

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Frequently Asked Questions

When should I plant Parsnip in Asotin County, WA?

Asotin County is in Zone 6b with an average last frost of May 9. Plan your Parsnip planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Asotin County, WA?

Asotin County, Washington is in USDA Hardiness Zone 6b. The average last spring frost is May 9 and first fall frost is September 30.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Asotin County gardeners in Zone 6b 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 Asotin County, WA. Local conditions may vary. Last updated: April 2026.