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When to Plant Potatoes in Tooele County, UT

Potatoes are a versatile staple crop that produces tubers underground. They come in hundreds of varieties with varying colors, textures, and maturity dates.

Tooele County, Utah is in USDA Zone 6a. The average last spring frost is May 1 and the first fall frost is October 17, giving you a growing season of approximately 169 days.

At an elevation of 4,309 feet, Tooele County receives approximately 12.6 inches of rainfall annually with predominantly loam soil. Summer highs average 89ยฐF, providing good warmth for Potatoes during the growing season. With low rainfall, drip irrigation is essential for growing Potatoes successfully. Mulch heavily to conserve soil moisture.

Tooele County, UT (Zone 6a) Moderate season
169 days
Last Spring Frost May 1
169 growing days
First Fall Frost October 17

Tooele County Soil Profile

Soil Type

Loam

Soil pH

6.3-7.8

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (15 days to spare)
Start indoors: Feb 28 Transplant: May 9 🍅 Harvest: Jul 18 – Sep 26
Recommended (50%) ✓ Fits season (15 days to spare)
Start indoors: Mar 6 Transplant: May 15 🍅 Harvest: Jul 24 – Oct 2
Safe Start (90%) ✓ Fits season (10 days to spare)
Start indoors: Mar 23 Transplant: Jun 1 🍅 Harvest: Aug 10 – Oct 19

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 Tooele County

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

Soil pH

Your soil pH (6.3โ€“7.8) is more alkaline than Potatoes prefers (5.0โ€“6.5). Add sulfur or peat moss to lower pH.

Soil Texture

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

Organic Matter

Organic matter is moderate (2.8%). Annual compost additions will help Potatoes.

How to Plant Potatoes

1"
Planting Depth
15"
Between Plants
24"
Between Rows

Succession Planting Potatoes

2
successive plantings in your 169-day season

Sow every 8 weeks. Last sowing by Jun 19 to harvest before frost.

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
0.3″/week
You supply
0.8″/week
Watering frequency 2-3 times/week
Season total 1,240 gal / 100 sq ft
Drought risk

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

Monthly Watering Guide for Potatoes

Potatoes needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.

Month Potatoes Needs Rainfall You Supplement Action
Jan โ€” 0.8" 0" โ„๏ธ Dormant
Feb โ€” 0.6" 0" โ„๏ธ Dormant
Mar โ€” 1.2" 0" โ„๏ธ Dormant
Apr โ€” 1.3" 0" โ„๏ธ Dormant
May 4.3" 1.5" 2.8" ๐Ÿšฟ Regular watering
Jun 4.3" 1" 3.3" ๐Ÿšฟ Regular watering
Jul 4.3" 1" 3.3" ๐Ÿšฟ Regular watering
Aug 4.3" 1.4" 2.9" ๐Ÿšฟ Regular watering
Sep 4.3" 1" 3.3" ๐Ÿšฟ Regular watering
Oct 4.3" 1.2" 3.1" ๐Ÿšฟ Regular watering
Nov โ€” 1" 0" โ„๏ธ Dormant
Dec โ€” 0.7" 0" โ„๏ธ Dormant

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

Potatoes 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.

Potatoes needs ~1,591 GDD — county provides 2,830 GDD Excellent fit

Potatoes Planting Timeline โ€” Tooele County, UT

Potatoes Planting Calendar

Activity When Date Range
Start Indoors March 6 Mar 6 โ€“ Mar 20
Transplant Outdoors May 15 May 15 โ€“ May 29
Direct Sow May 8 May 8 โ€“ May 29
Harvest July 24 Jul 24 โ€“ Oct 2

Plant 1" deep ยท 15" apart ยท Rows 24" apart

Month-by-Month Timeline

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

Growing Conditions

โ˜€๏ธ Sun

Full Sun (6-8+ hours)

๐Ÿ’ง Water

1"/week ยท 2-3 times/week

๐Ÿ“… Days to Maturity

70โ€“120 days

๐Ÿงช Soil pH

Needs 5โ€“6.5 ยท Your soil: too_alkaline

๐Ÿ—บ๏ธ USDA Zone

Zone 6a

๐Ÿ“† Growing Season

169 days in Tooele County

Growing Tips for Potatoes in Tooele County

Direct sow Potatoes outdoors after May 01 in Tooele County when soil has warmed and frost danger has passed.

Common pests for Potatoes in this region include tomato hornworm and aphids. Use row covers early in the season and inspect plants weekly.

Tooele County receives only 13" of rain annually. Potatoes needs consistent moisture โ€” install drip irrigation or water deeply 2-3 times per week.

General growing tips

Plant seed potatoes (not grocery store potatoes) 4 inches deep in spring. Hill soil around stems as plants grow to prevent greening. Stop watering when plants die back.

Companion Planting

Good Companions

Avoid Planting Near

  • Tomatoes
  • Cucumber
  • Squash Summer

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Potatoes in Tooele County, UT?

Tooele County is in Zone 6a with an average last frost of May 1. Plan your Potatoes planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Tooele County, UT?

Tooele County, Utah is in USDA Hardiness Zone 6a. The average last spring frost is May 1 and first fall frost is October 17.

๐ŸŒฑ

Plan Your Garden with Confidence

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