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When to Plant Carrots in Clark 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.

Clark County, Washington is in USDA Zone 8a. The average last spring frost is April 14 and the first fall frost is October 27, giving you a growing season of approximately 196 days.

At an elevation of 482 feet, Clark County receives approximately 39.9 inches of rainfall annually with predominantly silt loam soil. Summer highs average 85ยฐF, providing good warmth for Carrots during the growing season.

Clark County, WA (Zone 8a) Moderate season
196 days
Last Spring Frost April 14
196 growing days
First Fall Frost October 27

Clark County Soil Profile

Soil Type

Silt Loam

Soil pH

5.4-6.3

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (95 days to spare)
Transplant: Apr 8 🍅 Harvest: Jun 10 – Jul 15
Recommended (50%) ✓ Fits season (98 days to spare)
Transplant: Apr 14 🍅 Harvest: Jun 16 – Jul 21
Safe Start (90%) ✓ Fits season (96 days to spare)
Transplant: May 9 🍅 Harvest: Jul 11 – Aug 15

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.

Soil Compatibility in Clark County

How your county's soil matches Carrots's growing requirements.

Soil pH

Your soil pH (5.4โ€“6.3) is more acidic than Carrots prefers (6.0โ€“6.8). Add garden lime to raise pH.

Soil Texture

The silt loam soil in Clark County is excellent for Carrots โ€” good drainage, moisture retention, and nutrient holding capacity.

Drainage

Drainage is adequate for Carrots.

Organic Matter

Organic matter is excellent (4.8%) โ€” Carrots will thrive.

How to Plant Carrots

0.5"
Planting Depth
6"
Between Plants
12"
Between Rows

Fall planting: Sow 10 weeks before your first frost date for a fall harvest.

Succession Planting Carrots

3
successive plantings in your 196-day season

Sow every 6.9 weeks. Last sowing by Aug 08 to harvest before frost.

For a dedicated fall crop, sow by Aug 18.

Plant Water Budget

Plant needs
0.8″/week
Rainfall provides
0.9″/week
You supply
0.2″/week
Watering frequency Only during dry spells
Season total 323 gal / 100 sq ft

Monthly Watering Guide for Carrots

Carrots needs approximately 0.8 inches of water per week (3.5" per month). Here's how your county's rainfall compares month by month.

Month Carrots Needs Rainfall You Supplement Action
Jan โ€” 5.4" 0" โ„๏ธ Dormant
Feb โ€” 4.6" 0" โ„๏ธ Dormant
Mar โ€” 4" 0" โ„๏ธ Dormant
Apr 3.5" 2.6" 0.9" ๐Ÿ’ง Light watering
May 3.5" 2.5" 1" ๐Ÿ’ง Light watering
Jun 3.5" 1.7" 1.8" ๐Ÿšฟ Regular watering
Jul 3.5" 0.6" 2.9" ๐Ÿšฟ Regular watering
Aug 3.5" 0.8" 2.7" ๐Ÿšฟ Regular watering
Sep 3.5" 1.5" 2" ๐Ÿšฟ Regular watering
Oct 3.5" 3.1" 0.4" ๐Ÿ’ง Light watering
Nov โ€” 5.9" 0" โ„๏ธ Dormant
Dec โ€” 7.2" 0" โ„๏ธ Dormant

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

Carrots Heat Requirements (GDD)

What are Growing Degree Days (GDD)?

Growing Degree Days measure the total warmth your plants receive during the growing season. Think of it as a "heat bank" โ€” every day above 50ยฐF deposits warmth that helps your plants grow.

Each plant needs a certain amount of accumulated heat to mature. If your county provides more GDD than the plant needs, it's a great fit. If it's close, you may want to choose faster-maturing varieties or start seeds indoors to get a head start.

Carrots needs ~962 GDD — county provides 2,695 GDD Excellent fit

Carrots Planting Timeline โ€” Clark County, WA

Carrots Planting Calendar

Activity When Date Range
Direct Sow March 31 Mar 31 โ€“ Apr 21
Harvest June 2 Jun 2 โ€“ Jul 7
Fall Sowing August 18 Aug 18 โ€“ Sep 1

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

Month-by-Month Timeline

MonthActivities
January โ€”
February โ€”
March Direct Sow
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

0.8"/week ยท Only during dry spells

๐Ÿ“… Days to Maturity

60โ€“80 days

๐Ÿงช Soil pH

Needs 6โ€“6.8 ยท Your soil: too_acidic

๐Ÿ—บ๏ธ USDA Zone

Zone 8a

๐Ÿ“† Growing Season

196 days in Clark County

Growing Tips for Carrots in Clark County

Direct sow Carrots outdoors after April 14 in Clark County when soil has warmed and frost danger has passed.

Common pests for Carrots in this region include carrot rust fly and parsleyworm. Use row covers early in the season and inspect plants weekly.

General growing tips

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 Clark County, WA?

Clark County is in Zone 8a with an average last frost of April 14. Plan your Carrots planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Clark County, WA?

Clark County, Washington is in USDA Hardiness Zone 8a. The average last spring frost is April 14 and first fall frost is October 27.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Clark 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 Clark County, WA. Local conditions may vary. Last updated: April 2026.