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When to Plant Carrots in Coos 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.

Coos County, Oregon is in USDA Zone 8b. The average last spring frost is March 22 and the first fall frost is November 19, giving you a growing season of approximately 242 days.

At an elevation of 96 feet, Coos County receives approximately 38.8 inches of rainfall annually with predominantly silt loam soil. Summer highs average 89ยฐF, providing good warmth for Carrots during the growing season.

Coos County, OR (Zone 8b) Long season
242 days
Last Spring Frost March 22
242 growing days
First Fall Frost November 19

Coos County Soil Profile

Soil Type

Silt Loam

Soil pH

5.4-6.8

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (141 days to spare)
Transplant: Mar 7 🍅 Harvest: May 9 – Jun 13
Recommended (50%) ✓ Fits season (144 days to spare)
Transplant: Mar 22 🍅 Harvest: May 24 – Jun 28
Safe Start (90%) ✓ Fits season (139 days to spare)
Transplant: Apr 22 🍅 Harvest: Jun 24 – Jul 29

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 Coos County

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

Soil pH

Your soil pH (5.4โ€“6.8) overlaps with Carrots's range (6.0โ€“6.8), though not a perfect match.

Soil Texture

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

Organic Matter

Organic matter is excellent (5.7%) 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

4
successive plantings in your 242-day season

Sow every 6.9 weeks. Last sowing by Aug 31 to harvest before frost.

For a dedicated fall crop, sow by Sep 10.

Plant Water Budget

Plant needs
0.8″/week
Rainfall provides
0.7″/week
You supply
0.1″/week
Watering frequency Only during dry spells
Season total 273 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€” 5.5" 0" โ„๏ธ Dormant
Feb โ€” 4.5" 0" โ„๏ธ Dormant
Mar 3.5" 4.4" 0" โœ… Rainfall sufficient
Apr 3.5" 3.1" 0.4" ๐Ÿ’ง Light watering
May 3.5" 2.3" 1.2" ๐Ÿ’ง Light watering
Jun 3.5" 1.6" 1.9" 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" 1.4" 2.1" ๐Ÿšฟ Regular watering
Oct 3.5" 3.3" 0.2" ๐Ÿ’ง Light watering
Nov 3.5" 5.9" 0" โœ… Rainfall sufficient
Dec โ€” 5.5" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Marโ€“Nov in Coos 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 ~1,172 GDD — county provides 4,053 GDD Excellent fit

Carrots Planting Timeline โ€” Coos County, OR

Carrots Planting Calendar

Activity When Date Range
Direct Sow March 8 Mar 8 โ€“ Mar 29
Harvest May 10 May 10 โ€“ Jun 14
Fall Sowing September 10 Sep 10 โ€“ Sep 24

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

Month-by-Month Timeline

MonthActivities
January โ€”
February โ€”
March Direct Sow
April โ€”
May Harvest
June Harvest
July โ€”
August โ€”
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: acceptable

๐Ÿ—บ๏ธ USDA Zone

Zone 8b

๐Ÿ“† Growing Season

242 days in Coos County

Growing Tips for Carrots in Coos County

Direct sow Carrots outdoors after March 22 in Coos 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 Coos County, OR?

Coos County is in Zone 8b with an average last frost of March 22. Plan your Carrots planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Coos County, OR?

Coos County, Oregon is in USDA Hardiness Zone 8b. The average last spring frost is March 22 and first fall frost is November 19.

๐ŸŒฑ

Plan Your Garden with Confidence

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