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When to Plant Carrots in Fremont County, ID

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.

Fremont County, Idaho is in USDA Zone 4b. The average last spring frost is June 12 and the first fall frost is September 6, giving you a growing season of approximately 86 days.

At an elevation of 5,282 feet, Fremont County receives approximately 12.7 inches of rainfall annually with predominantly loam soil. Summer highs average 84ยฐF, so choose short-season varieties of Carrots to ensure they mature before fall. With low rainfall, drip irrigation is essential for growing Carrots successfully. Mulch heavily to conserve soil moisture.

Fremont County, ID (Zone 4b) Very short season
86 days
Last Spring Frost June 12
86 growing days
First Fall Frost September 6

Fremont County Soil Profile

Soil Type

Loam

Soil pH

6.4-8

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✗ May not fit
Transplant: May 23 🍅 Harvest: Jul 25 – Aug 29
Recommended (50%) ✗ May not fit
Transplant: Jun 12 🍅 Harvest: Aug 14 – Sep 18
Safe Start (90%) ✓ Fits season (0 days to spare)
Transplant: Jun 27 🍅 Harvest: Aug 29 – Oct 3

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
1.0″/week
Rainfall provides
0.6″/week
You supply
0.5″/week
Watering frequency 1-2 times/week
Season total 349 gal / 100 sq ft
Drought risk

Water stress score is 6/10 โ€” consider drought-tolerant varieties and mulching

Carrots needs ~910 GDD — county provides 1,118 GDD Good fit

Carrots Planting Timeline โ€” Fremont County, ID

Carrots Planting Calendar

Activity When Date Range
Direct Sow June 5 Jun 5 โ€“ Jun 26
Fall Sowing June 14 Jun 14 โ€“ Jun 28
Harvest August 7 Aug 7 โ€“ Sep 11

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

Month-by-Month Timeline

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

Growing Conditions

Sun

Full Sun (6-8+ hours)

Water

Moderate โ€” regular watering

Days to Maturity

60โ€“80 days

Soil pH

6 โ€“ 6.8

USDA Zone

Zone 4b

Growing Season

86 days

Growing Tips for Fremont 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

Level Up Your Garden

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 Fremont County, ID?

Fremont County is in Zone 4b with an average last frost of June 12. Plan your Carrots planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Fremont County, ID?

Fremont County, Idaho is in USDA Hardiness Zone 4b. The average last spring frost is June 12 and first fall frost is September 6.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Fremont County gardeners in Zone 4b 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 Fremont County, ID. Local conditions may vary. Last updated: April 2026.