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When to Plant Sunchoke in Pacific County, WA

Sunchokes (Jerusalem artichokes) are a native sunflower relative grown for their knobby, nutty-flavored tubers. They are extremely productive and nearly impossible to eradicate.

Pacific County, Washington is in USDA Zone 8b. The average last spring frost is April 18 and the first fall frost is October 29, giving you a growing season of approximately 194 days.

At an elevation of 14 feet, Pacific County receives approximately 47.4 inches of rainfall annually with predominantly silt loam soil. Summer highs average 86ยฐF, providing good warmth for Sunchoke during the growing season.

Pacific County, WA (Zone 8b) Moderate season
194 days
Last Spring Frost April 18
194 growing days
First Fall Frost October 29

Pacific County Soil Profile

Soil Type

Silt Loam

Soil pH

5.6-6.2

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (12 days to spare)
Transplant: Apr 19 🍅 Harvest: Aug 9 – Oct 4
Recommended (50%) ✓ Fits season (12 days to spare)
Transplant: May 2 🍅 Harvest: Aug 22 – Oct 17
Safe Start (90%) ✓ Fits season (25 days to spare)
Transplant: May 23 🍅 Harvest: Sep 12 – Nov 7

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
1.0″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft
Sunchoke needs ~1,885 GDD — county provides 2,813 GDD Excellent fit

Sunchoke Planting Timeline โ€” Pacific County, WA

Sunchoke Planting Calendar

Activity When Date Range
Transplant Outdoors May 2 May 2 โ€“ May 16
Harvest August 22 Aug 22 โ€“ Oct 17

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

Month-by-Month Timeline

MonthActivities
January โ€”
February โ€”
March โ€”
April โ€”
May Transplant Outdoors
June โ€”
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

110โ€“150 days

Soil pH

6 โ€“ 7.5

USDA Zone

Zone 8b

Growing Season

194 days

Growing Tips for Pacific County

Plant tubers 4 inches deep in early spring. Contain plants with barriers as they spread aggressively. Harvest after frost or leave in ground and dig as needed through winter.

Companion Planting

Good Companions

Level Up Your Garden

Frequently Asked Questions

When should I plant Sunchoke in Pacific County, WA?

Pacific County is in Zone 8b with an average last frost of April 18. Plan your Sunchoke planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Pacific County, WA?

Pacific County, Washington is in USDA Hardiness Zone 8b. The average last spring frost is April 18 and first fall frost is October 29.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Pacific County gardeners in Zone 8b organize planting dates, track what's growing, and never miss a planting window.

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Free download. Plan your entire garden season in minutes.

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