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When to Plant Carrots in Marion County, OR

Carrots are a popular root vegetable available in orange, purple, white, and yellow varieties. They are rich in beta-carotene and have a sweet, earthy flavor.

Marion County, Oregon is in USDA Zone 8a. The average last spring frost is April 20 and the first fall frost is October 30, giving you a growing season of approximately 193 days.

At an elevation of 422 feet, Marion County receives approximately 50.5 inches of rainfall annually with predominantly silt loam soil. Summer highs average 88ยฐF, providing good warmth for Carrots during the growing season. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Carrots root diseases.

Marion County, OR (Zone 8a) Moderate season
193 days
Last Spring Frost April 20
193 growing days
First Fall Frost October 30

Marion County Soil Profile

Soil Type

Silt Loam

Soil pH

5.4-6.8

Drainage

Well Drained

Monthly Watering Guide for Carrots

Carrots needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.

Month Carrots Needs Rainfall You Supplement Action
Jan โ€” 6.9" 0" โ„๏ธ Dormant
Feb โ€” 5.1" 0" โ„๏ธ Dormant
Mar โ€” 4.9" 0" โ„๏ธ Dormant
Apr 4.3" 3.8" 0.5" ๐Ÿ’ง Light watering
May 4.3" 2.8" 1.5" ๐Ÿ’ง Light watering
Jun 4.3" 2" 2.3" ๐Ÿšฟ Regular watering
Jul 4.3" 0.8" 3.5" ๐Ÿšฟ Regular watering
Aug 4.3" 1" 3.3" ๐Ÿšฟ Regular watering
Sep 4.3" 1.9" 2.4" ๐Ÿšฟ Regular watering
Oct 4.3" 4.2" 0.1" ๐Ÿ’ง Light watering
Nov โ€” 8.2" 0" โ„๏ธ Dormant
Dec โ€” 9" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Aprโ€“Oct in Marion County). Supplement amounts are based on average rainfall โ€” actual needs vary with temperature, soil, and mulching.

Carrots Planting Timeline โ€” Marion County, OR

Carrots Planting Calendar

Activity When Date Range
Direct Sow April 6 Apr 6 โ€“ Apr 27
Harvest June 8 Jun 8 โ€“ Jul 13
Fall Sowing August 21 Aug 21 โ€“ Sep 4

Plant 0.5" deep ยท 6" apart ยท Rows 12" apart

Month-by-Month Timeline

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

Growing Conditions

โ˜€๏ธ Sun

Full Sun (6-8+ hours)

๐Ÿ’ง Water

Moderate โ€” regular watering

๐Ÿ“… Days to Maturity

60โ€“80 days

๐Ÿงช Soil pH

Needs 6โ€“6.8 ยท Your soil: N/A

๐Ÿ—บ๏ธ USDA Zone

Zone 8a

๐Ÿ“† Growing Season

193 days in Marion County

Growing Tips for Marion County

Sow seeds directly in loose, stone-free soil for straight roots. Keep soil moist until germination which can take 2-3 weeks. Thin seedlings to 2 inches apart.

Companion Planting

Good Companions

Avoid Planting Near

  • Dill
  • Parsnip

Check more plant combinations with our Companion Planting Checker →

๐ŸŒพ Save Your Own Carrots Seeds
Life Cycle Biennial
Pollination Cross-Pollinated (insects)
How to Collect Replant roots for 2nd year flowers. Harvest umbels when brown.
Storage Store airtight; viable 3 years at 35ยฐF, under 50% humidity.

Isolate 1/2 mile from Queen Anne's Lace (wild carrot). Biennial โ€” requires two seasons.

Frequently Asked Questions

When should I plant Carrots in Marion County, OR?

Marion County is in Zone 8a with an average last frost of April 20. Plan your Carrots planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Marion County, OR?

Marion County, Oregon is in USDA Hardiness Zone 8a. The average last spring frost is April 20 and first fall frost is October 30.

๐ŸŒฑ

Plan Your Garden with Confidence

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

Get Your Free Garden Planner →

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 Marion County, OR. Local conditions may vary. Last updated: April 2026.