Blog

When to Plant Carrots in Columbia County, WA

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.

Columbia County, Washington is in USDA Zone 6b. The average last spring frost is April 28 and the first fall frost is October 11, giving you a growing season of approximately 166 days.

At an elevation of 3,157 feet, Columbia County receives approximately 21.4 inches of rainfall annually with predominantly silt loam soil. Summer highs average 90ยฐF, providing good warmth for Carrots during the growing season.

Columbia County, WA (Zone 6b) Moderate season
166 days
Last Spring Frost April 28
166 growing days
First Fall Frost October 11

Columbia County Soil Profile

Soil Type

Silt Loam

Soil pH

5.5-6.5

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€” 3" 0" โ„๏ธ Dormant
Feb โ€” 2.6" 0" โ„๏ธ Dormant
Mar โ€” 2.1" 0" โ„๏ธ Dormant
Apr 4.3" 1.7" 2.6" ๐Ÿšฟ Regular watering
May 4.3" 1.4" 2.9" ๐Ÿšฟ Regular watering
Jun 4.3" 0.9" 3.4" ๐Ÿšฟ Regular watering
Jul 4.3" 0.3" 4" ๐Ÿšฟ Regular watering
Aug 4.3" 0.3" 4" ๐Ÿšฟ Regular watering
Sep 4.3" 0.9" 3.4" ๐Ÿšฟ Regular watering
Oct 4.3" 1.9" 2.4" ๐Ÿšฟ Regular watering
Nov โ€” 3" 0" โ„๏ธ Dormant
Dec โ€” 3.4" 0" โ„๏ธ Dormant

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

Carrots Planting Timeline โ€” Columbia County, WA

Carrots Planting Calendar

Activity When Date Range
Direct Sow April 14 Apr 14 โ€“ May 5
Harvest June 16 Jun 16 โ€“ Jul 21
Fall Sowing August 2 Aug 2 โ€“ Aug 16

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 Direct Sow
June Harvest
July Harvest
August Fall Sowing
September โ€”
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 6b

๐Ÿ“† Growing Season

166 days in Columbia County

Growing Tips for Columbia 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 Columbia County, WA?

Columbia County is in Zone 6b with an average last frost of April 28. Plan your Carrots planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Columbia County, WA?

Columbia County, Washington is in USDA Hardiness Zone 6b. The average last spring frost is April 28 and first fall frost is October 11.

๐ŸŒฑ

Plan Your Garden with Confidence

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