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When to Plant Celeriac in Clatsop County, OR

Celeriac is a celery relative grown for its knobby, flavorful root rather than its stalks. It has a rich celery flavor and is excellent roasted, mashed, or in soups.

Clatsop County, Oregon is in USDA Zone 8b. The average last spring frost is April 12 and the first fall frost is November 4, giving you a growing season of approximately 206 days.

At an elevation of 412 feet, Clatsop County receives approximately 54.1 inches of rainfall annually with predominantly silt loam soil. Summer highs average 86ยฐF, providing good warmth for Celeriac during the growing season. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Celeriac root diseases.

Clatsop County, OR (Zone 8b) Long season
206 days
Last Spring Frost April 12
206 growing days
First Fall Frost November 4

Clatsop County Soil Profile

Soil Type

Silt Loam

Soil pH

5.6-6.7

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (70 days to spare)
Start indoors: Feb 25 Transplant: Apr 1 🍅 Harvest: Jul 15 – Aug 19
Recommended (50%) ✓ Fits season (66 days to spare)
Start indoors: Mar 8 Transplant: Apr 12 🍅 Harvest: Jul 26 – Aug 30
Safe Start (90%) ✓ Fits season (74 days to spare)
Start indoors: Mar 26 Transplant: Apr 30 🍅 Harvest: Aug 13 – Sep 17

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
1.5″/week
Rainfall provides
1.1″/week
You supply
0.4″/week
Watering frequency 1-2 times/week
Season total 728 gal / 100 sq ft
Celeriac needs ~1,595 GDD — county provides 2,987 GDD Excellent fit

Celeriac Planting Timeline โ€” Clatsop County, OR

Celeriac Planting Calendar

Activity When Date Range
Start Indoors March 8 Mar 8 โ€“ Mar 22
Transplant Outdoors April 12 Apr 12 โ€“ Apr 26
Direct Sow March 29 Mar 29 โ€“ Apr 19
Fall Sowing August 26 Aug 26 โ€“ Sep 9
Harvest July 26 Jul 26 โ€“ Aug 30

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

Month-by-Month Timeline

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

Growing Conditions

Sun

Full Sun (6-8+ hours)

Water

High โ€” keep soil consistently moist

Days to Maturity

100โ€“120 days

Soil pH

6 โ€“ 7

USDA Zone

Zone 8b

Growing Season

206 days

Growing Tips for Clatsop County

Start seeds indoors 10-12 weeks before last frost. Remove side roots as they develop to encourage a single large bulb. Harvest after a light frost for best flavor.

Companion Planting

Good Companions

Avoid Planting Near

  • Carrots
  • Parsnip

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Frequently Asked Questions

When should I plant Celeriac in Clatsop County, OR?

Clatsop County is in Zone 8b with an average last frost of April 12. Plan your Celeriac planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Clatsop County, OR?

Clatsop County, Oregon is in USDA Hardiness Zone 8b. The average last spring frost is April 12 and first fall frost is November 4.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Clatsop County gardeners in Zone 8b 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 Clatsop County, OR. Local conditions may vary. Last updated: April 2026.