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When to Plant Arugula in Carbon County, UT

Arugula is a fast-growing cool-season green with a peppery, nutty flavor. It is excellent in salads and can be harvested as baby greens or mature leaves.

Carbon County, Utah is in USDA Zone 5b. The average last spring frost is May 17 and the first fall frost is September 27, giving you a growing season of approximately 133 days.

At an elevation of 5,755 feet, Carbon County receives approximately 14.2 inches of rainfall annually with predominantly loam soil. Summer highs average 84ยฐF, so choose short-season varieties of Arugula to ensure they mature before fall. With low rainfall, drip irrigation is essential for growing Arugula successfully. Mulch heavily to conserve soil moisture.

Carbon County, UT (Zone 5b) Short season
133 days
Last Spring Frost May 17
133 growing days
First Fall Frost September 27

Carbon County Soil Profile

Soil Type

Loam

Soil pH

6.4-8.3

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (39 days to spare)
Start indoors: Apr 2 Transplant: May 7 🍅 Harvest: Jun 11 – Aug 13
Recommended (50%) ✓ Fits season (35 days to spare)
Start indoors: Apr 12 Transplant: May 17 🍅 Harvest: Jun 21 – Aug 23
Safe Start (90%) ✓ Fits season (28 days to spare)
Start indoors: May 4 Transplant: Jun 8 🍅 Harvest: Jul 13 – Sep 14

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
0.5″/week
You supply
0.7″/week
Watering frequency 1-2 times/week
Season total 783 gal / 100 sq ft
Drought risk

Water stress score is 8/10 โ€” consider drought-tolerant varieties and mulching

Arugula needs ~520 GDD — county provides 1,729 GDD Excellent fit

Arugula Planting Timeline โ€” Carbon County, UT

Arugula Planting Calendar

Activity When Date Range
Start Indoors April 12 Apr 12 โ€“ Apr 26
Transplant Outdoors May 17 May 17 โ€“ May 31
Direct Sow May 3 May 3 โ€“ May 24
Fall Sowing July 19 Jul 19 โ€“ Aug 2
Harvest June 21 Jun 21 โ€“ Aug 23

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

Month-by-Month Timeline

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

Growing Conditions

Sun

Partial Shade (3-6 hours)

Water

Moderate โ€” regular watering

Days to Maturity

30โ€“50 days

Soil pH

6 โ€“ 7

USDA Zone

Zone 5b

Growing Season

133 days

Growing Tips for Carbon County

Sow seeds directly every 2-3 weeks for continuous harvest. Provide afternoon shade in warm weather to prevent bolting. Harvest outer leaves first to extend production.

Companion Planting

Good Companions

Avoid Planting Near

  • Strawberries

Level Up Your Garden

Frequently Asked Questions

When should I plant Arugula in Carbon County, UT?

Carbon County is in Zone 5b with an average last frost of May 17. Plan your Arugula planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Carbon County, UT?

Carbon County, Utah is in USDA Hardiness Zone 5b. The average last spring frost is May 17 and first fall frost is September 27.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Carbon County gardeners in Zone 5b organize planting dates, track what's growing, and never miss a planting window.

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Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Carbon County, UT. Local conditions may vary. Last updated: April 2026.